diff --git a/.github/actions/on_host_tests/action.yaml b/.github/actions/on_host_tests/action.yaml
index b4e7f74e91ab..a8c33f90a6ce 100644
--- a/.github/actions/on_host_tests/action.yaml
+++ b/.github/actions/on_host_tests/action.yaml
@@ -35,17 +35,17 @@ runs:
         env
 
         # Explicitly point to libraries in extracted dir.
-        LD_LIBRARY_PATH="${test_dir}/out/${{ matrix.platform }}_${{ matrix.config }}/starboard"
-        LD_LIBRARY_PATH="${LD_LIBRARY_PATH}:${test_dir}/out/${{ matrix.platform }}_${{ matrix.config }}"
+        LD_LIBRARY_PATH="${test_dir}/starboard"
+        LD_LIBRARY_PATH="${LD_LIBRARY_PATH}:${test_dir}"
         export LD_LIBRARY_PATH
 
         # Make results dir available to the archiving step below.
         results_dir="${GITHUB_WORKSPACE}/results"
         echo "results_dir=${results_dir}" >> $GITHUB_ENV
 
+        failed_suites=""
         cd ${test_dir}
-        for test_binary_path in $(ls -d out/**/*tests out/**/nplb); do
-          test_binary=$(basename "${test_binary_path}")
+        for test_binary in $(ls {*tests,nplb}); do
           echo "Running tests for suite: ${test_binary}"
 
           test_filter="*"
@@ -57,9 +57,16 @@ runs:
           echo "Test filter evaluated to: ${test_filter}"
 
           xml_path="${results_dir}/${test_binary}_testoutput.xml"
-          /usr/bin/xvfb-run -a --server-args="${XVFB_SERVER_ARGS}" ./$test_binary_path --gtest_filter="${test_filter}" --gtest_output="xml:${xml_path}"
+          /usr/bin/xvfb-run -a --server-args="${XVFB_SERVER_ARGS}" "./${test_binary}" --gtest_filter="${test_filter}" --gtest_output="xml:${xml_path}" || {
+            # Set exit code on failure.
+            failed_suites="${failed_suites} ${test_binary}"
+          }
         done
         echo "Finished running all unit tests..."
+        if [ -n "${failed_suites}" ]; then
+          echo "Test suites failed:${failed_suites}"
+          exit 1
+        fi
     - name: Archive Test Results
       if: success() || failure()
       uses: actions/upload-artifact@v4
diff --git a/.github/actions/process_test_results/action.yaml b/.github/actions/process_test_results/action.yaml
index 89a2f13a5d42..bce228e5ad79 100644
--- a/.github/actions/process_test_results/action.yaml
+++ b/.github/actions/process_test_results/action.yaml
@@ -10,18 +10,23 @@ inputs:
 runs:
   using: "composite"
   steps:
-    - name: Download Artifacts
+    - name: Download Test Results
       uses: actions/download-artifact@v4
       with:
         name: ${{ inputs.test_results_key }}
         path: results/
 
-    - name: Publish Test Report
+    - name: Test Summary action
       continue-on-error: true
-      uses: mikepenz/action-junit-report@992d97d6eb2e5f3de985fbf9df6a04386874114d
+      uses: test-summary/action@31493c76ec9e7aa675f1585d3ed6f1da69269a86
       with:
-        report_paths: results/*.xml
-        annotate_only: true
+        paths: "results/*.xml"
+        output: test-report-summary.md
+        show: "fail, skip"
+
+    - name: Output test summary markdown to github
+      run: cat test-report-summary.md >> $GITHUB_STEP_SUMMARY
+      shell: bash
 
     - name: Get Datadog CLI
       id: download-dd-cli
diff --git a/.github/actions/upload_test_artifacts/action.yaml b/.github/actions/upload_test_artifacts/action.yaml
index 53402606ee34..017950dce2ff 100644
--- a/.github/actions/upload_test_artifacts/action.yaml
+++ b/.github/actions/upload_test_artifacts/action.yaml
@@ -31,13 +31,20 @@ runs:
       if: inputs.on_host == 'true'
       run: |
         set -x
-        cd src
-        tar cvf - out/${{ matrix.platform }}_${{ matrix.config }}/*tests out/${{ matrix.platform }}_${{ matrix.config }}/nplb out/${{ matrix.platform }}_${{ matrix.config }}/*.so out/${{ matrix.platform }}_${{ matrix.config }}/*.so.* out/${{ matrix.platform }}_${{ matrix.config }}/starboard/*.so.* out/${{ matrix.platform }}_${{ matrix.config }}/content/test | xz -T0 -1 -z - > test_artifacts.tar.xz
+        cd src/out/${{ matrix.platform }}_${{ matrix.config }}
+        test_deps_file="test.deps"
+        for test_binary in $(ls {nplb,*tests}); do
+          echo $test_binary
+          if [ -f "${test_binary}.runtime_deps" ]; then
+            cat "${test_binary}.runtime_deps" >> "${test_deps_file}"
+          fi
+        done
+        tar cvf - -T "${test_deps_file}" | xz -T0 -1 -z - > "${GITHUB_WORKSPACE}/test_artifacts.tar.xz"
       shell: bash
     - name: Upload On-Host Test Artifacts Archive
       if: inputs.on_host == 'true'
       uses: actions/upload-artifact@v4
       with:
         name: ${{ inputs.test_artifacts_key }}
-        path: src/test_artifacts.tar.xz
+        path: test_artifacts.tar.xz
         retention-days: 3
diff --git a/.github/workflows/main.yaml b/.github/workflows/main.yaml
index 963d6e253402..bfd96b5d001c 100644
--- a/.github/workflows/main.yaml
+++ b/.github/workflows/main.yaml
@@ -133,7 +133,7 @@ jobs:
       matrix:
         platform: ${{ fromJson(needs.initialize.outputs.platforms) }}
         include: ${{ fromJson(needs.initialize.outputs.includes) }}
-        config: [devel, debug, qa, gold]
+        config: [devel, qa, gold]
     container: ${{ needs.docker-build-image.outputs.docker_tag }}
     env:
       TEST_ARTIFACTS_KEY: ${{ matrix.platform }}_${{ matrix.name }}_test_artifacts
@@ -156,7 +156,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
         # TODO(bug?): android debug builds are broken.
-        if: ${{ ! (startsWith(matrix.platform, 'android') && matrix.config == 'debug') }}
+        if: ${{ ! (contains(matrix.platform, 'android') && matrix.config == 'debug') }}
         with:
           path: src
           # Use fetch depth of 0 to get full history for a valid build id.
@@ -164,7 +164,7 @@ jobs:
       - name: Build Cobalt
         uses: ./src/.github/actions/build
         # TODO(bug?): android debug builds are broken.
-        if: ${{ ! (startsWith(matrix.platform, 'android') && matrix.config == 'debug') }}
+        if: ${{ ! (contains(matrix.platform, 'android') && matrix.config == 'debug') }}
         with:
           targets: ${{ needs.initialize.outputs.targets }}
       - name: Upload Test Artifacts
diff --git a/build/build_config.h b/build/build_config.h
index 4d7d0d984343..0a6d93b878b5 100644
--- a/build/build_config.h
+++ b/build/build_config.h
@@ -284,7 +284,7 @@
 #define BUILDFLAG_INTERNAL_MODULAR_BUILD() (0)
 #endif
 
-#if defined(COBALT_IS_RELEASE_BUILD)
+#if defined(ENABLE_BUILDFLAG_COBALT_IS_RELEASE_BUILD)
 #define BUILDFLAG_INTERNAL_COBALT_IS_RELEASE_BUILD() (1)
 #else
 #define BUILDFLAG_INTERNAL_COBALT_IS_RELEASE_BUILD() (0)
diff --git a/cobalt/BUILD.gn b/cobalt/BUILD.gn
index 646d29c54acc..0e8901255339 100644
--- a/cobalt/BUILD.gn
+++ b/cobalt/BUILD.gn
@@ -77,16 +77,18 @@ action("cobalt_build_info") {
   ]
 }
 
-test("cobalt_unittests") {
-  testonly = true
+if (is_android) {
+  test("cobalt_unittests") {
+    testonly = true
 
-  sources = [ "//cobalt/user_agent/user_agent_platform_info_test.cc" ]
+    sources = [ "//cobalt/user_agent/user_agent_platform_info_test.cc" ]
 
-  deps = [
-    "//base/test:run_all_unittests",
-    "//cobalt/user_agent",
-    "//starboard:starboard_group",
-    "//testing/gmock",
-    "//testing/gtest",
-  ]
+    deps = [
+      "//base/test:run_all_unittests",
+      "//cobalt/user_agent",
+      "//starboard:starboard_group",
+      "//testing/gmock",
+      "//testing/gtest",
+    ]
+  }
 }
diff --git a/cobalt/android/BUILD.gn b/cobalt/android/BUILD.gn
index 85e5e0d69d75..eb9b6249f6ae 100644
--- a/cobalt/android/BUILD.gn
+++ b/cobalt/android/BUILD.gn
@@ -32,13 +32,21 @@ jinja_template("cobalt_manifest") {
   variables = [ "manifest_package=dev.cobalt.coat" ]
 }
 
+generate_jni("jni_headers") {
+  sources = [ "apk/app/src/main/java/dev/cobalt/coat/StarboardBridge.java" ]
+}
+
 # TODO(cobalt): Re-enable or remove disabled java files.
 android_library("cobalt_apk_java") {
   testonly = true
   resources_package = "dev.cobalt.coat"
+  annotation_processor_deps = [ "//base/android/jni_generator:jni_processor" ]
+
   deps = [
     ":cobalt_java_resources",
+    ":jni_headers",
     "//base:base_java",
+    "//base:jni_java",
     "//base:process_launcher_java",
     "//build/android:build_java",
     "//components/embedder_support/android:view_java",
@@ -57,6 +65,7 @@ android_library("cobalt_apk_java") {
     "//ui/android:ui_no_recycler_view_java",
     "//url:gurl_java",
   ]
+
   sources = [
     "apk/app/src/app/java/dev/cobalt/app/CobaltApplication.java",
     "apk/app/src/app/java/dev/cobalt/app/MainActivity.java",
@@ -202,7 +211,6 @@ content_shell_apk_tmpl("cobalt_apk") {
     ":cobalt_apk_java",
   ]
   shared_libraries = [ ":libcobalt_content_shell_content_view" ]
-  command_line_flags_file = "content-shell-command-line"
   include_size_info = is_official_build
 }
 
diff --git a/cobalt/android/apk/app/src/main/java/dev/cobalt/coat/CobaltActivity.java b/cobalt/android/apk/app/src/main/java/dev/cobalt/coat/CobaltActivity.java
index 84bae40f70b3..5b2b75e133b8 100644
--- a/cobalt/android/apk/app/src/main/java/dev/cobalt/coat/CobaltActivity.java
+++ b/cobalt/android/apk/app/src/main/java/dev/cobalt/coat/CobaltActivity.java
@@ -35,7 +35,6 @@
 import android.widget.LinearLayout;
 import android.widget.Toast;
 import androidx.annotation.Nullable;
-import dev.cobalt.app.CobaltApplication;
 import dev.cobalt.coat.javabridge.CobaltJavaScriptAndroidObject;
 import dev.cobalt.coat.javabridge.CobaltJavaScriptInterface;
 import dev.cobalt.coat.javabridge.H5vccPlatformService;
@@ -102,13 +101,10 @@ public abstract class CobaltActivity extends Activity {
   protected void createContent(final Bundle savedInstanceState) {
     // Initializing the command line must occur before loading the library.
     if (!CommandLine.isInitialized()) {
-      ((CobaltApplication) getApplication()).initCommandLine();
+      CommandLine.init(null);
 
-      // Note that appendSwitchesAndArguments excludes cobaltCommandLineParams[0]
-      // as the program name, and all other arguments SHOULD start with '--'.
       String[] cobaltCommandLineParams =
           new String[] {
-            "",
             // Disable first run experience.
             "--disable-fre",
             // Disable user prompts in the first run.
@@ -476,6 +472,11 @@ protected void onStop() {
     getStarboardBridge().onActivityStop(this);
     super.onStop();
 
+    WebContents webContents = getActiveWebContents();
+    if (webContents != null) {
+      webContents.onHide();
+    }
+
     if (VideoSurfaceView.getCurrentSurface() != null) {
       forceCreateNewVideoSurfaceView = true;
     }
diff --git a/cobalt/android/apk/app/src/main/java/dev/cobalt/coat/StarboardBridge.java b/cobalt/android/apk/app/src/main/java/dev/cobalt/coat/StarboardBridge.java
index d94590f00523..1c2ab30c339d 100644
--- a/cobalt/android/apk/app/src/main/java/dev/cobalt/coat/StarboardBridge.java
+++ b/cobalt/android/apk/app/src/main/java/dev/cobalt/coat/StarboardBridge.java
@@ -26,11 +26,7 @@
 import android.hardware.input.InputManager;
 import android.media.AudioDeviceInfo;
 import android.media.AudioManager;
-import android.net.ConnectivityManager;
-import android.net.Network;
-import android.net.NetworkCapabilities;
 import android.os.Build;
-import android.util.Pair;
 import android.util.Size;
 import android.util.SizeF;
 import android.view.Display;
@@ -44,16 +40,16 @@
 import dev.cobalt.util.Log;
 import dev.cobalt.util.UsedByNative;
 import java.lang.reflect.Method;
-import java.net.InterfaceAddress;
-import java.net.NetworkInterface;
-import java.net.SocketException;
 import java.util.Calendar;
-import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.Locale;
 import java.util.TimeZone;
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.base.annotations.JNINamespace;
+import org.chromium.base.annotations.NativeMethods;
 
 /** Implementation of the required JNI methods called by the Starboard C++ code. */
+@JNINamespace("starboard::android::shared")
 public class StarboardBridge {
 
   /** Interface to be implemented by the Android Application hosting the starboard app. */
@@ -144,7 +140,19 @@ public StarboardBridge(
 
   private native void closeNativeStarboard(long nativeApp);
 
-  private native long nativeCurrentMonotonicTime();
+  @NativeMethods
+    interface Natives {
+        void onStop();
+
+        long currentMonotonicTime();
+
+        // TODO(cobalt, b/372559388): move below native methods to the Natives interface.
+        // boolean initJNI();
+
+        // long startNativeStarboard();
+
+        // void closeNativeStarboard(long nativeApp);
+    }
 
   protected void onActivityStart(Activity activity) {
     Log.e(TAG, "onActivityStart ran");
@@ -160,16 +168,14 @@ protected void onActivityStop(Activity activity) {
       activityHolder.set(null);
     }
     sysConfigChangeReceiver.setForeground(false);
-    afterStopped();
   }
 
-  private native void nativeOnStop();
-
   protected void onActivityDestroy(Activity activity) {
     if (applicationStopped) {
       // We can't restart the starboard app, so kill the process for a clean start next time.
       Log.i(TAG, "Activity destroyed after shutdown; killing app.");
       closeNativeStarboard(nativeApp);
+      closeAllServices();
       System.exit(0);
     } else {
       Log.i(TAG, "Activity destroyed without shutdown; app suspended in background.");
@@ -186,8 +192,6 @@ protected void onServiceDestroy(Service service) {
     }
   }
 
-  @SuppressWarnings("unused")
-  @UsedByNative
   protected void beforeStartOrResume() {
     Log.i(TAG, "Prepare to resume");
     // Bring our platform services to life before resuming so that they're ready to deal with
@@ -201,8 +205,6 @@ protected void beforeStartOrResume() {
     advertisingId.refresh();
   }
 
-  @SuppressWarnings("unused")
-  @UsedByNative
   protected void beforeSuspend() {
     try {
       Log.i(TAG, "Prepare to suspend");
@@ -219,14 +221,19 @@ protected void beforeSuspend() {
     }
   }
 
-  @SuppressWarnings("unused")
-  @UsedByNative
-  protected void afterStopped() {
-    applicationStopped = true;
+  private void closeAllServices() {
     ttsHelper.shutdown();
     for (CobaltService service : cobaltServices.values()) {
       service.afterStopped();
     }
+  }
+
+  // Warning: "Stopped" refers to Starboard "Stopped" event, it's different from Android's "onStop".
+  @SuppressWarnings("unused")
+  @CalledByNative
+  protected void afterStopped() {
+    applicationStopped = true;
+    closeAllServices();
     Activity activity = activityHolder.get();
     if (activity != null) {
       // Wait until the activity is destroyed to exit.
@@ -240,18 +247,20 @@ protected void afterStopped() {
   }
 
   @SuppressWarnings("unused")
-  @UsedByNative
+  @CalledByNative
   protected void applicationStarted() {
     applicationReady = true;
   }
 
   @SuppressWarnings("unused")
-  @UsedByNative
+  @CalledByNative
   protected void applicationStopping() {
     applicationReady = false;
     applicationStopped = true;
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/system_request_conceal.cc
   @SuppressWarnings("unused")
   @UsedByNative
   public void requestSuspend() {
@@ -272,6 +281,7 @@ public boolean onSearchRequested() {
 
   // private native boolean nativeOnSearchRequested();
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
   @SuppressWarnings("unused")
   @UsedByNative
   public Context getApplicationContext() {
@@ -281,6 +291,8 @@ public Context getApplicationContext() {
     return appContext;
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/system_platform_error.cc
   @SuppressWarnings("unused")
   @UsedByNative
   void raisePlatformError(@PlatformError.ErrorType int errorType, long data) {
@@ -302,7 +314,7 @@ protected Holder<Activity> getActivityHolder() {
   }
 
   @SuppressWarnings("unused")
-  @UsedByNative
+  @CalledByNative
   protected String[] getArgs() {
     if (args == null) {
       throw new IllegalArgumentException("args cannot be null");
@@ -312,7 +324,7 @@ protected String[] getArgs() {
 
   /** Returns the URL from the Intent that started the app. */
   @SuppressWarnings("unused")
-  @UsedByNative
+  @CalledByNative
   protected String getStartDeepLink() {
     if (startDeepLink == null) {
       throw new IllegalArgumentException("startDeepLink cannot be null");
@@ -335,6 +347,8 @@ private void nativeHandleDeepLink(String url) {
     // TODO(b/374147993): Implement deep link
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/file_internal.cc
   /**
    * Returns the absolute path to the directory where application specific files should be written.
    * May be overridden for use cases that need to segregate storage.
@@ -345,6 +359,8 @@ protected String getFilesAbsolutePath() {
     return appContext.getFilesDir().getAbsolutePath();
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/file_internal.cc
   /**
    * Returns the absolute path to the application specific cache directory on the filesystem. May be
    * overridden for use cases that need to segregate storage.
@@ -355,59 +371,8 @@ protected String getCacheAbsolutePath() {
     return appContext.getCacheDir().getAbsolutePath();
   }
 
-  /**
-   * Returns non-loopback network interface address and its netmask, or null if none.
-   *
-   * <p>A Java function to help implement Starboard's SbSocketGetLocalInterfaceAddress.
-   */
-  @SuppressWarnings("unused")
-  @UsedByNative
-  Pair<byte[], byte[]> getLocalInterfaceAddressAndNetmask(boolean wantIPv6) {
-    try {
-      Enumeration<NetworkInterface> it = NetworkInterface.getNetworkInterfaces();
-
-      while (it.hasMoreElements()) {
-        NetworkInterface ni = it.nextElement();
-        if (ni.isLoopback()) {
-          continue;
-        }
-        if (!ni.isUp()) {
-          continue;
-        }
-        if (ni.isPointToPoint()) {
-          continue;
-        }
-
-        for (InterfaceAddress ia : ni.getInterfaceAddresses()) {
-          byte[] address = ia.getAddress().getAddress();
-          boolean isIPv6 = (address.length > 4);
-          if (isIPv6 == wantIPv6) {
-            // Convert the network prefix length to a network mask.
-            int prefix = ia.getNetworkPrefixLength();
-            byte[] netmask = new byte[address.length];
-            for (int i = 0; i < netmask.length; i++) {
-              if (prefix == 0) {
-                netmask[i] = 0;
-              } else if (prefix >= 8) {
-                netmask[i] = (byte) 0xFF;
-                prefix -= 8;
-              } else {
-                netmask[i] = (byte) (0xFF << (8 - prefix));
-                prefix = 0;
-              }
-            }
-            return new Pair<>(address, netmask);
-          }
-        }
-      }
-    } catch (SocketException ex) {
-      // TODO should we have a logging story that strips logs for production?
-      Log.w(TAG, "sbSocketGetLocalInterfaceAddress exception", ex);
-      return null;
-    }
-    return null;
-  }
-
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/speech_synthesis_speak.cc
   @SuppressWarnings("unused")
   @UsedByNative
   CobaltTextToSpeechHelper getTextToSpeechHelper() {
@@ -417,6 +382,8 @@ CobaltTextToSpeechHelper getTextToSpeechHelper() {
     return ttsHelper;
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/accessibility_get_caption_settings.cc
   /**
    * @return A new CaptionSettings object with the current system caption settings.
    */
@@ -428,6 +395,8 @@ CaptionSettings getCaptionSettings() {
     return new CaptionSettings(cm);
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/system_get_locale_id.cc
   /** Java-layer implementation of SbSystemGetLocaleId. */
   @SuppressWarnings("unused")
   @UsedByNative
@@ -435,6 +404,8 @@ String systemGetLocaleId() {
     return Locale.getDefault().toLanguageTag();
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/time_zone_get_name.cc
   @SuppressWarnings("unused")
   @UsedByNative
   String getTimeZoneId() {
@@ -447,18 +418,19 @@ String getTimeZoneId() {
     return timeZone.getID();
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/window_get_diagonal_size_in_inches.cc
   @SuppressWarnings("unused")
   @UsedByNative
   SizeF getDisplayDpi() {
     return DisplayUtil.getDisplayDpi();
   }
 
-  @SuppressWarnings("unused")
-  @UsedByNative
   Size getDisplaySize() {
     return DisplayUtil.getSystemDisplaySize();
   }
 
+  // TODO: (cobalt b/372559388) migrate JNI.
   @SuppressWarnings("unused")
   @UsedByNative
   public ResourceOverlay getResourceOverlay() {
@@ -481,6 +453,8 @@ private static String getSystemProperty(String name) {
     }
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/window_get_size.cc
   @SuppressWarnings("unused")
   @UsedByNative
   Size getDeviceResolution() {
@@ -505,6 +479,8 @@ Size getDeviceResolution() {
     }
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/system_network_is_disconnected.cc
   @SuppressWarnings("unused")
   @UsedByNative
   boolean isNetworkConnected() {
@@ -514,6 +490,8 @@ boolean isNetworkConnected() {
     return networkStatus.isConnected();
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/microphone_impl.cc
   /**
    * Checks if there is no microphone connected to the system.
    *
@@ -543,6 +521,8 @@ public boolean isMicrophoneDisconnected() {
     return true;
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/microphone_impl.cc
   /**
    * Checks if the microphone is muted.
    *
@@ -555,26 +535,8 @@ public boolean isMicrophoneMute() {
     return audioManager.isMicrophoneMute();
   }
 
-  /**
-   * @return true if we have an active network connection and it's on an wireless network.
-   */
-  @SuppressWarnings("unused")
-  @UsedByNative
-  boolean isCurrentNetworkWireless() {
-    ConnectivityManager connMgr =
-        (ConnectivityManager) appContext.getSystemService(Context.CONNECTIVITY_SERVICE);
-    Network activeNetwork = connMgr.getActiveNetwork();
-    if (activeNetwork == null) {
-      return false;
-    }
-    NetworkCapabilities activeCapabilities = connMgr.getNetworkCapabilities(activeNetwork);
-    if (activeCapabilities == null) {
-      return false;
-    }
-    // Consider anything that's not definitely wired to be wireless.
-    return !activeCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET);
-  }
-
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/accessibility_get_display_settings.cc
   /**
    * @return true if the user has enabled accessibility high contrast text in the operating system.
    */
@@ -593,6 +555,8 @@ boolean isAccessibilityHighContrastTextEnabled() {
     }
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/android_media_session_client.cc
   @SuppressWarnings("unused")
   @UsedByNative
   void updateMediaSession(
@@ -612,6 +576,8 @@ void updateMediaSession(
     //     playbackState, actions, positionMs, speed, title, artist, album, artwork, duration);
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/android_media_session_client.cc
   @SuppressWarnings("unused")
   @UsedByNative
   public void deactivateMediaSession() {
@@ -620,6 +586,8 @@ public void deactivateMediaSession() {
     // cobaltMediaSession.deactivateMediaSession();
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/system_get_property.cc
   /** Returns string for kSbSystemPropertyUserAgentAuxField */
   @SuppressWarnings("unused")
   @UsedByNative
@@ -648,6 +616,8 @@ protected String getUserAgentAuxField() {
     return sb.toString();
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/system_get_property.cc
   /** Returns string for kSbSystemPropertyAdvertisingId */
   @SuppressWarnings("unused")
   @UsedByNative
@@ -655,6 +625,8 @@ protected String getAdvertisingId() {
     return this.advertisingId.getId();
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/system_get_property.cc
   /** Returns boolean for kSbSystemPropertyLimitAdTracking */
   @SuppressWarnings("unused")
   @UsedByNative
@@ -662,6 +634,8 @@ protected boolean getLimitAdTracking() {
     return this.advertisingId.isLimitAdTrackingEnabled();
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/audio_track_bridge.cc
   @SuppressWarnings("unused")
   @UsedByNative
   AudioOutputManager getAudioOutputManager() {
@@ -682,6 +656,8 @@ AudioOutputManager getAudioOutputManager() {
   //   audioPermissionRequester.onRequestPermissionsResult(requestCode, permissions, grantResults);
   // }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/video_window.cc
   @SuppressWarnings("unused")
   @UsedByNative
   public void resetVideoSurface() {
@@ -691,6 +667,8 @@ public void resetVideoSurface() {
     }
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/player_set_bounds.cc
   @SuppressWarnings("unused")
   @UsedByNative
   public void setVideoSurfaceBounds(final int x, final int y, final int width, final int height) {
@@ -700,9 +678,11 @@ public void setVideoSurfaceBounds(final int x, final int y, final int width, fin
     }
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/media_capabilities_cache.cc
   /** Return supported hdr types. */
   @SuppressWarnings("unused")
-  @UsedByNative
+  @CalledByNative
   public int[] getSupportedHdrTypes() {
     Display defaultDisplay = DisplayUtil.getDefaultDisplay();
     if (defaultDisplay == null) {
@@ -778,14 +758,15 @@ public byte[] sendToCobaltService(String serviceName, byte [] data) {
     return response.data;
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
   /** Returns the application start timestamp. */
   @SuppressWarnings("unused")
-  @UsedByNative
+  @CalledByNative
   protected long getAppStartTimestamp() {
     Activity activity = activityHolder.get();
     if (activity instanceof CobaltActivity) {
       long javaStartTimestamp = ((CobaltActivity) activity).getAppStartTimestamp();
-      long cppTimestamp = nativeCurrentMonotonicTime();
+      long cppTimestamp = StarboardBridgeJni.get().currentMonotonicTime();
       long javaStopTimestamp = System.nanoTime();
       return cppTimestamp
           - (javaStopTimestamp - javaStartTimestamp) / timeNanosecondsPerMicrosecond;
@@ -793,6 +774,8 @@ protected long getAppStartTimestamp() {
     return 0;
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/graphics.cc
   @SuppressWarnings("unused")
   @UsedByNative
   void reportFullyDrawn() {
@@ -802,6 +785,8 @@ void reportFullyDrawn() {
     }
   }
 
+  // TODO: (cobalt b/372559388) remove or migrate JNI?
+  // Used in starboard/android/shared/crash_handler.cc
   @SuppressWarnings("unused")
   @UsedByNative
   public void setCrashContext(String key, String value) {
@@ -821,19 +806,19 @@ public void registerCrashContextUpdateHandler(CrashContextUpdateHandler handler)
   }
 
   @SuppressWarnings("unused")
-  @UsedByNative
+  @CalledByNative
   protected boolean getIsAmatiDevice() {
     return this.isAmatiDevice;
   }
 
   @SuppressWarnings("unused")
-  @UsedByNative
+  @CalledByNative
   protected String getBuildFingerprint() {
     return Build.FINGERPRINT;
   }
 
   @SuppressWarnings("unused")
-  @UsedByNative
+  @CalledByNative
   protected long getPlayServicesVersion() {
     try {
       if (android.os.Build.VERSION.SDK_INT < 28) {
diff --git a/cobalt/build/configs/BUILD.gn b/cobalt/build/configs/BUILD.gn
index 81f47ec01aac..c731b81109d0 100644
--- a/cobalt/build/configs/BUILD.gn
+++ b/cobalt/build/configs/BUILD.gn
@@ -55,6 +55,6 @@ config("buildflag_defines") {
     defines += [ "ENABLE_BUILDFLAG_MODULAR_BUILD" ]
   }
   if (cobalt_is_release_build) {
-    defines += [ "COBALT_IS_RELEASE_BUILD" ]
+    defines += [ "ENABLE_BUILDFLAG_COBALT_IS_RELEASE_BUILD" ]
   }
 }
diff --git a/cobalt/build/gn.py b/cobalt/build/gn.py
index 998ee7d942af..8e34d4e2b7c7 100755
--- a/cobalt/build/gn.py
+++ b/cobalt/build/gn.py
@@ -56,7 +56,6 @@ def get_build_args(build_args_path):
     },
     'qa': {
         'symbol_level': 1,
-        'is_debug': 'false',
         'is_official_build': 'true'
     },
     'gold': {
diff --git a/cobalt/cobalt_content_browser_client.cc b/cobalt/cobalt_content_browser_client.cc
index 11fbc9641bc7..8b612b359872 100644
--- a/cobalt/cobalt_content_browser_client.cc
+++ b/cobalt/cobalt_content_browser_client.cc
@@ -83,11 +83,11 @@ blink::UserAgentMetadata CobaltContentBrowserClient::GetUserAgentMetadata() {
 void CobaltContentBrowserClient::OverrideWebkitPrefs(
     content::WebContents* web_contents,
     blink::web_pref::WebPreferences* prefs) {
-#if !defined(OFFICIAL_BUILD)
+#if !defined(COBALT_IS_RELEASE_BUILD)
   // Allow creating a ws: connection on a https: page to allow current
   // testing set up. See b/377410179.
   prefs->allow_running_insecure_content = true;
-#endif  // !defined(OFFICIAL_BUILD)
+#endif  // !defined(COBALT_IS_RELEASE_BUILD)
   content::ShellContentBrowserClient::OverrideWebkitPrefs(web_contents, prefs);
 }
 
diff --git a/cobalt/devinfra/kokoro/bin/cleanup.sh b/cobalt/devinfra/kokoro/bin/cleanup.sh
index 725d0f29ef98..7df9b12f3c0a 100755
--- a/cobalt/devinfra/kokoro/bin/cleanup.sh
+++ b/cobalt/devinfra/kokoro/bin/cleanup.sh
@@ -1,12 +1,10 @@
 set -x
 
-REPO_ROOT="$(dirname "$0")/../../.."
 # After kokoro build finishes, changed files in c:/tmpfs get rsync'ed to a borg executor,
 # from where the artifacts and reports are processed.
 # Especially on Windows, the rsync can take long time, so we cleanup the cobalt workspace
 # after finishing each build.
 set +e
-pushd $REPO_ROOT
-time git clean -fdx
-popd
+git config --global --add safe.directory "${WORKSPACE_COBALT}"
+time git -C "${WORKSPACE_COBALT}" clean -dfx
 exit 0
diff --git a/cobalt/devinfra/kokoro/bin/common.sh b/cobalt/devinfra/kokoro/bin/common.sh
index aff77e3c3704..eed0bbd9f3f5 100755
--- a/cobalt/devinfra/kokoro/bin/common.sh
+++ b/cobalt/devinfra/kokoro/bin/common.sh
@@ -265,19 +265,9 @@ create_and_upload_nightly_archive () {
   fi
   local gcs_archive_path="gs://$(get_bucket_name)/${platform}${gcs_path_suffix}/$(date +%F)/${KOKORO_ROOT_BUILD_NUMBER}/"
 
-  # Creates nightly archive from package directory.
-  python3 "${WORKSPACE_COBALT}/tools/create_archive.py" \
-    -s "${package_dir}" \
-    -d "${local_archive_path}" \
-    --intermediate
-
   init_gcloud
 
-  # Uploads nightly archive.
-  "${GSUTIL}" cp "${local_archive_path}" "${gcs_archive_path}"
-
-  # Uploads build_info.json.
-  "${GSUTIL}" cp "${build_info_path}" "${gcs_archive_path}"
+  "${GSUTIL}" cp -r "${package_dir}" "${gcs_archive_path}"
 }
 
 run_package_release_pipeline () {
@@ -300,11 +290,7 @@ run_package_release_pipeline () {
 
     # Create release package.
     if [[ "${PLATFORM}" =~ "android" ]]; then
-      # Creates Android package directory.
-      python3 "${WORKSPACE_COBALT}/cobalt/devinfra/kokoro/build/android/simple_packager.py" \
-        "${out_dir}" \
-        "${package_dir}" \
-        "${WORKSPACE_COBALT}"
+      cp "${out_dir}/apks/Cobalt.apk" "${package_dir}"
     elif [[ "${PLATFORM}" =~ "evergreen" ]]; then
       local bootloader_out_dir=
       if [ -n "${BOOTLOADER:-}" ]; then
@@ -316,8 +302,7 @@ run_package_release_pipeline () {
         "${package_dir}" \
         "${bootloader_out_dir:-}"
     else
-      # Sets package directory as out directory.
-      package_dir="${out_dir}"
+      cp "${out_dir}/cobalt" "${package_dir}"
     fi
 
     # Create and upload nightly archive.
diff --git a/cobalt/devinfra/kokoro/bin/dind_build.sh b/cobalt/devinfra/kokoro/bin/dind_build.sh
index cc41bed4a4d0..7d4e6dc9969a 100755
--- a/cobalt/devinfra/kokoro/bin/dind_build.sh
+++ b/cobalt/devinfra/kokoro/bin/dind_build.sh
@@ -8,13 +8,11 @@
 # Kokoro Instance
 # └── Generic DinD Image
 #     ├── dind_builder_runner.sh
-#     │   ├── configure_environment (common.sh)
 #     │   ├── main_build_image_and_run.py
 #     │   │   └── Specific Cobalt Image
 #     │   │       └── dind_build.sh                             <= THIS SCRIPT
 #     │   └── run_package_release_pipeline (common.sh)
 #     └── dind_runner.sh
-#         ├── configure_environment (common.sh)
 #         ├── main_pull_image_and_run.py
 #         │   └── Specific Cobalt Image
 #         │       └── dind_build.sh                             <= THIS SCRIPT
@@ -42,10 +40,6 @@ fi
 # Load common routines (we only need run_gn and ninja_build).
 . $(dirname "$0")/common.sh
 
-WORKSPACE_COBALT="${KOKORO_ARTIFACTS_DIR}/git/src"
-
-configure_environment
-
 pipeline () {
   local out_dir="${WORKSPACE_COBALT}/out/${TARGET_PLATFORM}_${CONFIG}"
   local gclient_root="${KOKORO_ARTIFACTS_DIR}/chromium"
diff --git a/cobalt/devinfra/kokoro/bin/dind_builder_runner.sh b/cobalt/devinfra/kokoro/bin/dind_builder_runner.sh
index 302a395106d0..b9135d48b334 100755
--- a/cobalt/devinfra/kokoro/bin/dind_builder_runner.sh
+++ b/cobalt/devinfra/kokoro/bin/dind_builder_runner.sh
@@ -9,13 +9,11 @@
 # Kokoro Instance
 # └── Generic DinD Image
 #     ├── dind_builder_runner.sh                              <== THIS SCRIPT
-#     │   ├── configure_environment (common.sh)
 #     │   ├── main_build_image_and_run.py
 #     │   │   └── Specific Cobalt Image
 #     │   │       └── dind_build.sh
 #     │   └── run_package_release_pipeline (common.sh)
 #     └── dind_runner.sh
-#         ├── configure_environment (common.sh)
 #         ├── main_pull_image_and_run.py
 #         │   └── Specific Cobalt Image
 #         │       └── dind_build.sh
@@ -27,15 +25,12 @@ set -ueEx
 
 # Using repository root as work directory.
 export WORKSPACE_COBALT="${KOKORO_ARTIFACTS_DIR}/git/src"
-cd "${WORKSPACE_COBALT}"
 
 # Clean up workspace on exit or error.
 trap "bash ${WORKSPACE_COBALT}/cobalt/devinfra/kokoro/bin/cleanup.sh" EXIT INT TERM
 
 configure_dind_environment
 
-configure_environment
-
 set -x
 # The python script is responsible for running containerized Cobalt builds.
 python3 "${WORKSPACE_COBALT}/cobalt/devinfra/kokoro/bin/dind_py/main_build_image_and_run.py"
diff --git a/cobalt/devinfra/kokoro/bin/dind_py/dind_common.py b/cobalt/devinfra/kokoro/bin/dind_py/dind_common.py
index 94b4df0eafc2..d6bb8f367b37 100644
--- a/cobalt/devinfra/kokoro/bin/dind_py/dind_common.py
+++ b/cobalt/devinfra/kokoro/bin/dind_py/dind_common.py
@@ -31,10 +31,6 @@
 # within the inner Docker container.
 _INTERNAL_KOKORO_BUILD_SCRIPT = 'cobalt/devinfra/kokoro/bin/dind_build.sh'
 
-_WORKSPACE_COBALT_VAR = 'WORKSPACE_COBALT'
-
-_SERVICE_NOT_FOUND = 'SERVICE_NOT_FOUND'
-
 _PLATFORM_TO_SERVICE_MAP = {
     'android-x86': 'linux',
     'android-arm': 'linux',
@@ -70,7 +66,7 @@ def push_image(target_image):
   utils.exec_cmd(command)
 
 
-def get_local_image_name(service, compose_file='docker-compose.yaml'):
+def get_local_image_name(service, compose_file):
   """
   Parses the docker-compose file to determine the image-name from the
   service-name. When the compose-file is used to build the image, it will get
@@ -90,9 +86,7 @@ def tag_image(src_img, dest_img):
   utils.exec_cmd(tag_command)
 
 
-def run_docker_build(platform,
-                     target_image,
-                     compose_file='docker-compose.yaml'):
+def run_docker_build(platform, target_image, compose_file):
   """
   Runs the docker build for the provided platform, and tags the newly built
   image with the registry/image/tag arguments. If the build fails, instead it
diff --git a/cobalt/devinfra/kokoro/bin/dind_py/main_build_image_and_run.py b/cobalt/devinfra/kokoro/bin/dind_py/main_build_image_and_run.py
index a3f3cd07be90..46fb9bccf981 100644
--- a/cobalt/devinfra/kokoro/bin/dind_py/main_build_image_and_run.py
+++ b/cobalt/devinfra/kokoro/bin/dind_py/main_build_image_and_run.py
@@ -24,13 +24,11 @@
    Kokoro Instance
    └── Generic DinD Image
        ├── dind_builder_runner.sh
-       │   ├── configure_environment (common.sh)
        │   ├── main_build_image_and_run.py                      <= THIS SCRIPT
        │   │   └── Specific Cobalt Image
        │   │       └── dind_build.sh
        │   └── run_package_release_pipeline (common.sh)
        └── dind_runner.sh
-           ├── configure_environment (common.sh)
            ├── main_pull_image_and_run.py
            │   └── Specific Cobalt Image
            │       └── dind_build.sh
@@ -95,7 +93,8 @@ def main():
       utils.logging_info_spacer('Building Docker Image')
       build_start_time = time.time()
       try:
-        dind.run_docker_build(args.platform, target_image)
+        dind.run_docker_build(args.platform, target_image,
+                              args.src_root + '/docker-compose.yaml')
         dind.tag_image(target_image, floating_image)
         dind.push_image(floating_image)
         docker_build_duration = time.time() - build_start_time
diff --git a/cobalt/devinfra/kokoro/bin/dind_py/main_pull_image_and_run.py b/cobalt/devinfra/kokoro/bin/dind_py/main_pull_image_and_run.py
index a7e14582f22c..852c11137c7b 100644
--- a/cobalt/devinfra/kokoro/bin/dind_py/main_pull_image_and_run.py
+++ b/cobalt/devinfra/kokoro/bin/dind_py/main_pull_image_and_run.py
@@ -21,13 +21,11 @@
    Kokoro Instance
    └── Generic DinD Image
        ├── dind_builder_runner.sh
-       │   ├── configure_environment (common.sh)
        │   ├── main_build_image_and_run.py
        │   │   └── Specific Cobalt Image
        │   │       └── dind_build.sh
        │   └── run_package_release_pipeline (common.sh)
        └── dind_runner.sh
-           ├── configure_environment (common.sh)
            ├── main_pull_image_and_run.py                       <= THIS SCRIPT
            │   └── Specific Cobalt Image
            │       └── dind_build.sh
diff --git a/cobalt/devinfra/kokoro/bin/dind_runner.sh b/cobalt/devinfra/kokoro/bin/dind_runner.sh
index 157aa6141caa..ed0534e236e6 100755
--- a/cobalt/devinfra/kokoro/bin/dind_runner.sh
+++ b/cobalt/devinfra/kokoro/bin/dind_runner.sh
@@ -9,13 +9,11 @@
 # Kokoro Instance
 # └── Generic DinD Image
 #     ├── dind_builder_runner.sh
-#     │   ├── configure_environment (common.sh)
 #     │   ├── main_build_image_and_run.py
 #     │   │   └── Specific Cobalt Image
 #     │   │       └── dind_build.sh
 #     │   └── run_package_release_pipeline (common.sh)
 #     └── dind_runner.sh                                    <== THIS SCRIPT
-#         ├── configure_environment (common.sh)
 #         ├── main_pull_image_and_run.py
 #         │   └── Specific Cobalt Image
 #         │       └── dind_build.sh
@@ -27,15 +25,12 @@ set -ueEx
 
 # Using repository root as work directory.
 export WORKSPACE_COBALT="${KOKORO_ARTIFACTS_DIR}/git/src"
-cd "${WORKSPACE_COBALT}"
 
 # Clean up workspace on exit or error.
 trap "bash ${WORKSPACE_COBALT}/cobalt/devinfra/kokoro/bin/cleanup.sh" EXIT INT TERM
 
 configure_dind_environment
 
-configure_environment
-
 set -x
 # The python script is responsible for running containerized Cobalt builds.
 python3 "${WORKSPACE_COBALT}/cobalt/devinfra/kokoro/bin/dind_py/main_pull_image_and_run.py"
diff --git a/cobalt/devinfra/kokoro/docker-compose.yaml b/cobalt/devinfra/kokoro/docker-compose.yaml
index 20800f61d970..756943ab3479 100644
--- a/cobalt/devinfra/kokoro/docker-compose.yaml
+++ b/cobalt/devinfra/kokoro/docker-compose.yaml
@@ -56,6 +56,7 @@ services:
       SCCACHE_GCS_OAUTH_URL: ${SCCACHE_GCS_OAUTH_URL}
       SCCACHE_GCS_RW_MODE: ${SCCACHE_GCS_RW_MODE}
       SCCACHE_IDLE_TIMEOUT: ${SCCACHE_IDLE_TIMEOUT}
+      WORKSPACE_COBALT: ${WORKSPACE_COBALT}
       # Kokoro Specific Variables to forward:
       KOKORO_ARTIFACTS_DIR: ${KOKORO_ARTIFACTS_DIR}
       KOKORO_BUILD_ARTIFACTS_SUBDIR: ${KOKORO_BUILD_ARTIFACTS_SUBDIR}
diff --git a/cobalt/user_agent/BUILD.gn b/cobalt/user_agent/BUILD.gn
index e019640ad639..21fa26c5ebc3 100644
--- a/cobalt/user_agent/BUILD.gn
+++ b/cobalt/user_agent/BUILD.gn
@@ -12,6 +12,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+if (is_android) {
+  import("//build/config/android/abi.gni")
+}
+
 static_library("user_agent") {
   sources = [
     "user_agent_platform_info.cc",
@@ -24,4 +28,11 @@ static_library("user_agent") {
     "//starboard/common",
     "//v8:v8_version",
   ]
+
+  if (is_android) {
+    defines = [
+      # Enable compile-time decisions based on the ABI
+      "ANDROID_ABI=$android_app_abi",
+    ]
+  }
 }
diff --git a/content/browser/BUILD.gn b/content/browser/BUILD.gn
index 7824a83f0a7f..7e224c74a664 100644
--- a/content/browser/BUILD.gn
+++ b/content/browser/BUILD.gn
@@ -2321,6 +2321,13 @@ source_set("browser") {
     "worker_host/worker_script_loader_factory.h",
   ]
 
+  if (is_cobalt) {
+    sources += [
+      "cobalt/crash_annotator/crash_annotator_impl.cc",
+      "cobalt/crash_annotator/crash_annotator_impl.h",
+    ]
+  }
+
   if (use_starscan) {
     sources += [
       "starscan_load_observer.cc",
diff --git a/content/browser/browser_interface_binders.cc b/content/browser/browser_interface_binders.cc
index 90bd74a313bf..78da69eda21c 100644
--- a/content/browser/browser_interface_binders.cc
+++ b/content/browser/browser_interface_binders.cc
@@ -174,6 +174,11 @@
 #include "third_party/blink/public/public_buildflags.h"
 #include "url/origin.h"
 
+#if BUILDFLAG(IS_COBALT)
+#include "content/browser/cobalt/crash_annotator/crash_annotator_impl.h"
+#include "third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom.h"
+#endif
+
 #if BUILDFLAG(IS_ANDROID)
 #include "content/browser/android/date_time_chooser_android.h"
 #include "content/browser/android/text_suggestion_host_android.h"
@@ -841,6 +846,11 @@ void PopulateFrameBinders(RenderFrameHostImpl* host, mojo::BinderMap* map) {
   map->Add<blink::mojom::SpeechSynthesis>(base::BindRepeating(
       &RenderFrameHostImpl::GetSpeechSynthesis, base::Unretained(host)));
 
+#if BUILDFLAG(IS_COBALT)
+  map->Add<blink::mojom::CrashAnnotator>(base::BindRepeating(
+    &RenderFrameHostImpl::GetCrashAnnotator, base::Unretained(host)));
+#endif
+
 #if !BUILDFLAG(IS_ANDROID)
   map->Add<blink::mojom::DeviceAPIService>(base::BindRepeating(
       &RenderFrameHostImpl::GetDeviceInfoService, base::Unretained(host)));
diff --git a/content/browser/cobalt/crash_annotator/crash_annotator_impl.cc b/content/browser/cobalt/crash_annotator/crash_annotator_impl.cc
new file mode 100644
index 000000000000..72bb36a25658
--- /dev/null
+++ b/content/browser/cobalt/crash_annotator/crash_annotator_impl.cc
@@ -0,0 +1,31 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "content/browser/cobalt/crash_annotator/crash_annotator_impl.h"
+
+#include "base/functional/bind.h"
+#include "base/functional/callback.h"
+
+namespace content {
+
+void CrashAnnotatorImpl::SetString(const std::string& key,
+                                   const std::string& value,
+                                   SetStringCallback callback) {
+  // TODO(cobalt, b/383301493): actually implement this.
+  LOG(INFO) << "CrashAnnotatorImpl::SetString key=" << key << " value="
+            << value;
+  std::move(callback).Run(false);
+}
+
+}  // namespace content
diff --git a/content/browser/cobalt/crash_annotator/crash_annotator_impl.h b/content/browser/cobalt/crash_annotator/crash_annotator_impl.h
new file mode 100644
index 000000000000..2573de92f779
--- /dev/null
+++ b/content/browser/cobalt/crash_annotator/crash_annotator_impl.h
@@ -0,0 +1,47 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef CONTENT_BROWSER_CRASH_ANNOTATOR_IMPL_H_
+#define CONTENT_BROWSER_CRASH_ANNOTATOR_IMPL_H_
+
+#include <string>
+
+#include "mojo/public/cpp/bindings/pending_receiver.h"
+#include "mojo/public/cpp/bindings/receiver.h"
+#include "third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom.h"
+
+namespace content {
+
+// TODO(cobalt, b/383301493): consider another location for Cobalt's Mojo
+// implementations, since they are not "core" services. mcasas@ suggested
+// //components or //services as possible destinations.
+class CrashAnnotatorImpl : public blink::mojom::CrashAnnotator {
+ public:
+  explicit CrashAnnotatorImpl(
+      mojo::PendingReceiver<blink::mojom::CrashAnnotator> receiver)
+      : receiver_(this, std::move(receiver)) {}
+  CrashAnnotatorImpl(const CrashAnnotatorImpl&) = delete;
+  CrashAnnotatorImpl& operator=(const CrashAnnotatorImpl&) = delete;
+
+  void SetString(const std::string& key,
+                 const std::string& value,
+                 SetStringCallback callback) override;
+
+ private:
+  mojo::Receiver<blink::mojom::CrashAnnotator> receiver_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_CRASH_ANNOTATOR_IMPL_H_
diff --git a/content/browser/renderer_host/render_frame_host_impl.cc b/content/browser/renderer_host/render_frame_host_impl.cc
index 3b35cc5d4492..be77a68af476 100644
--- a/content/browser/renderer_host/render_frame_host_impl.cc
+++ b/content/browser/renderer_host/render_frame_host_impl.cc
@@ -269,6 +269,10 @@
 #include "url/origin.h"
 #include "url/url_constants.h"
 
+#if BUILDFLAG(IS_COBALT)
+#include "content/browser/cobalt/crash_annotator/crash_annotator_impl.h"
+#endif
+
 #if BUILDFLAG(IS_ANDROID)
 #include "content/browser/android/content_url_loader_factory.h"
 #include "content/browser/android/java_interfaces_impl.h"
@@ -11593,6 +11597,13 @@ void RenderFrameHostImpl::GetFileSystemManager(
                                 storage_key(), std::move(receiver)));
 }
 
+#if BUILDFLAG(IS_COBALT)
+void RenderFrameHostImpl::GetCrashAnnotator(
+    mojo::PendingReceiver<blink::mojom::CrashAnnotator> receiver) {
+  crash_annotator_ = std::make_unique<CrashAnnotatorImpl>(std::move(receiver));
+}
+#endif
+
 void RenderFrameHostImpl::GetGeolocationService(
     mojo::PendingReceiver<blink::mojom::GeolocationService> receiver) {
   if (!geolocation_service_) {
diff --git a/content/browser/renderer_host/render_frame_host_impl.h b/content/browser/renderer_host/render_frame_host_impl.h
index 0c61e60b8a11..52c56fd94333 100644
--- a/content/browser/renderer_host/render_frame_host_impl.h
+++ b/content/browser/renderer_host/render_frame_host_impl.h
@@ -172,6 +172,11 @@
 #include "ui/gfx/geometry/rect.h"
 #include "url/gurl.h"
 
+#if BUILDFLAG(IS_COBALT)
+#include "third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom-forward.h"
+#include "third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom.h"
+#endif
+
 #if BUILDFLAG(IS_ANDROID)
 #include "base/containers/id_map.h"
 #include "services/device/public/mojom/nfc.mojom.h"
@@ -249,6 +254,9 @@ class DocumentServiceBase;
 class AgentSchedulingGroupHost;
 class BrowsingContextState;
 class CodeCacheHostImpl;
+#if BUILDFLAG(IS_COBALT)
+class CrashAnnotatorImpl;
+#endif
 class CrossOriginEmbedderPolicyReporter;
 class CrossOriginOpenerPolicyAccessReportManager;
 class FeatureObserver;
@@ -1942,6 +1950,11 @@ class CONTENT_EXPORT RenderFrameHostImpl
   void GetFileSystemAccessManager(
       mojo::PendingReceiver<blink::mojom::FileSystemAccessManager> receiver);
 
+#if BUILDFLAG(IS_COBALT)
+  void GetCrashAnnotator(
+      mojo::PendingReceiver<blink::mojom::CrashAnnotator> receiver);
+#endif
+
 #if !BUILDFLAG(IS_ANDROID)
   void GetHidService(mojo::PendingReceiver<blink::mojom::HidService> receiver);
 
@@ -4492,6 +4505,10 @@ class CONTENT_EXPORT RenderFrameHostImpl
   // Tracks the document policy which has been set on this frame.
   std::unique_ptr<blink::DocumentPolicy> document_policy_;
 
+#if BUILDFLAG(IS_COBALT)
+  std::unique_ptr<CrashAnnotatorImpl> crash_annotator_;
+#endif
+
 #if BUILDFLAG(IS_ANDROID)
   // An InterfaceProvider for Java-implemented interfaces that are scoped to
   // this RenderFrameHost. This provides access to interfaces implemented in
diff --git a/media/filters/chunk_demuxer.cc b/media/filters/chunk_demuxer.cc
index 6b2410f99d9f..7778437a2ec5 100644
--- a/media/filters/chunk_demuxer.cc
+++ b/media/filters/chunk_demuxer.cc
@@ -172,6 +172,9 @@ void ChunkDemuxerStream::Seek(base::TimeDelta time) {
   DCHECK(state_ == UNINITIALIZED || state_ == RETURNING_ABORT_FOR_READS)
       << state_;
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+  write_head_ = time;
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
   stream_->Seek(time);
 }
 
@@ -217,6 +220,13 @@ bool ChunkDemuxerStream::EvictCodedFrames(base::TimeDelta media_time,
   return stream_->GarbageCollectIfNeeded(media_time, newDataSize);
 }
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+base::TimeDelta ChunkDemuxerStream::GetWriteHead() const {
+  base::AutoLock auto_lock(lock_);
+  return write_head_;
+}
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
 void ChunkDemuxerStream::OnMemoryPressure(
     base::TimeDelta media_time,
     base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level,
@@ -490,6 +500,13 @@ void ChunkDemuxerStream::CompletePendingReadIfPossible_Locked() {
   // Other cases are kOk and just return the buffers.
   DCHECK(!buffers.empty());
   requested_buffer_count_ = 0;
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+  for (auto&& buffer : buffers) {
+    if (!buffer->end_of_stream()) {
+      write_head_ = std::max(write_head_, buffer->timestamp());
+    }
+  }
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
   std::move(read_cb_).Run(kOk, std::move(buffers));
 }
 
@@ -1051,6 +1068,22 @@ bool ChunkDemuxer::EvictCodedFrames(const std::string& id,
   return itr->second->EvictCodedFrames(currentMediaTime, newDataSize);
 }
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+base::TimeDelta ChunkDemuxer::GetWriteHead(const std::string& id) const {
+  base::AutoLock auto_lock(lock_);
+  DCHECK(IsValidId_Locked(id));
+
+  auto iter = id_to_streams_map_.find(id);
+  if (iter == id_to_streams_map_.end() || iter->second.empty()) {
+    // Handled just in case.
+    NOTREACHED();
+    return base::TimeDelta();
+  }
+
+  return iter->second[0]->GetWriteHead();
+}
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
 bool ChunkDemuxer::AppendToParseBuffer(const std::string& id,
                                        const uint8_t* data,
                                        size_t length) {
diff --git a/media/filters/chunk_demuxer.h b/media/filters/chunk_demuxer.h
index 49b7199e0943..fb66b32bfcb0 100644
--- a/media/filters/chunk_demuxer.h
+++ b/media/filters/chunk_demuxer.h
@@ -83,6 +83,12 @@ class MEDIA_EXPORT ChunkDemuxerStream : public DemuxerStream {
   // https://w3c.github.io/media-source/#sourcebuffer-coded-frame-eviction
   bool EvictCodedFrames(base::TimeDelta media_time, size_t newDataSize);
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+  // Returns the latest presentation timestamp of the buffers queued in the
+  // stream.
+  base::TimeDelta GetWriteHead() const;
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
   void OnMemoryPressure(
       base::TimeDelta media_time,
       base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level,
@@ -190,6 +196,7 @@ class MEDIA_EXPORT ChunkDemuxerStream : public DemuxerStream {
 
 #if BUILDFLAG(USE_STARBOARD_MEDIA)
   const std::string mime_type_;
+  base::TimeDelta write_head_ GUARDED_BY(lock_);
 #endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
 
   // Specifies the type of the stream.
@@ -416,6 +423,12 @@ class MEDIA_EXPORT ChunkDemuxer : public Demuxer {
                                       base::TimeDelta currentMediaTime,
                                       size_t newDataSize);
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+  // Returns the latest presentation timestamp of the buffers to be read
+  // from the DemuxerStream.
+  [[nodiscard]] base::TimeDelta GetWriteHead(const std::string& id) const;
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
   void OnMemoryPressure(
       base::TimeDelta currentMediaTime,
       base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level,
diff --git a/media/starboard/starboard_renderer.cc b/media/starboard/starboard_renderer.cc
index 4ed2ed2426f9..9be127ea9fd9 100644
--- a/media/starboard/starboard_renderer.cc
+++ b/media/starboard/starboard_renderer.cc
@@ -592,9 +592,11 @@ void StarboardRenderer::OnDemuxerStreamRead(
       DCHECK(audio_read_in_progress_);
       audio_read_in_progress_ = false;
       for (const auto& buffer : buffers) {
-        last_audio_sample_interval_ =
-            buffer->timestamp() - timestamp_of_last_written_audio_;
-        timestamp_of_last_written_audio_ = buffer->timestamp();
+        if (!buffer->end_of_stream()) {
+          last_audio_sample_interval_ =
+              buffer->timestamp() - timestamp_of_last_written_audio_;
+          timestamp_of_last_written_audio_ = buffer->timestamp();
+        }
       }
       player_bridge_->WriteBuffers(DemuxerStream::AUDIO, buffers);
     } else {
diff --git a/starboard/CHANGELOG.md b/starboard/CHANGELOG.md
index 6df4a1fdb3b4..14a2ba33fe30 100644
--- a/starboard/CHANGELOG.md
+++ b/starboard/CHANGELOG.md
@@ -50,6 +50,13 @@ It was only used by win32 platforms
 ### Removed starboad/atomic.h support for C.
 The existing code was migrated to C11 atomics.
 
+### Renamed `SbMediaIs*Supported()` functions
+`SbMediaIsAudioSupported()`, `SbMediaIsSupported()`, and
+`SbMediaIsVideoSupported()` were never part of the Starboard interface.
+Their Sb prefixes were removed and renamed to `MediaIsAudioSupported()`,
+`MediaIsSupported()`, and `MediaIsVideoSupported()`.  They are also moved from
+the global namespace into ::starboard::shared::starboard::media.
+
 ## Version 16
 A key update in Starboard version 16 is the adoption of POSIX APIs.
 For a full overview of Starboard POSIX migrations, please refer to
diff --git a/starboard/android/arm/platform_configuration/configuration.gni b/starboard/android/arm/platform_configuration/configuration.gni
index 77e2920e49a6..1cfa2ddb08c1 100644
--- a/starboard/android/arm/platform_configuration/configuration.gni
+++ b/starboard/android/arm/platform_configuration/configuration.gni
@@ -14,7 +14,6 @@
 
 import("//starboard/android/shared/platform_configuration/configuration.gni")
 
-android_abi = "armeabi-v7a"
 arm_float_abi = "softfp"
 
 sb_evergreen_compatible_package = true
diff --git a/starboard/android/arm64/platform_configuration/configuration.gni b/starboard/android/arm64/platform_configuration/configuration.gni
index 34daf92deb12..12583a39a513 100644
--- a/starboard/android/arm64/platform_configuration/configuration.gni
+++ b/starboard/android/arm64/platform_configuration/configuration.gni
@@ -14,6 +14,5 @@
 
 import("//starboard/android/shared/platform_configuration/configuration.gni")
 
-android_abi = "arm64-v8a"
 sabi_path = "//starboard/sabi/arm64/sabi-v$sb_api_version.json"
 sb_evergreen_compatible_package = true
diff --git a/starboard/android/shared/BUILD.gn b/starboard/android/shared/BUILD.gn
index eef374515f49..cf4b70c4dd9f 100644
--- a/starboard/android/shared/BUILD.gn
+++ b/starboard/android/shared/BUILD.gn
@@ -103,7 +103,6 @@ static_library("starboard_platform") {
     "//starboard/shared/starboard/command_line.cc",
     "//starboard/shared/starboard/command_line.h",
     "//starboard/shared/starboard/decode_target/decode_target_get_info.cc",
-    "//starboard/shared/starboard/decode_target/decode_target_internal.cc",
     "//starboard/shared/starboard/decode_target/decode_target_internal.h",
     "//starboard/shared/starboard/decode_target/decode_target_release.cc",
     "//starboard/shared/starboard/drm/drm_close_session.cc",
@@ -265,6 +264,8 @@ static_library("starboard_platform") {
     #"speech_synthesis_internal.cc",
     #"speech_synthesis_is_supported.cc",
     #"speech_synthesis_speak.cc",
+    "starboard_bridge.cc",
+    "starboard_bridge.h",
     "system_get_extensions.cc",
     "system_get_locale_id.cc",
     "system_get_path.cc",
@@ -316,12 +317,14 @@ static_library("starboard_platform") {
   public_deps = [
     ":starboard_base_symbolize",
     ":starboard_jni_state",
+    "//cobalt/android:jni_headers",
     "//starboard/common",
     "//starboard/shared/starboard/media:media_util",
     "//starboard/shared/starboard/player/filter:filter_based_player_sources",
   ]
 
   deps = [
+    "//base",
     "//third_party/libevent",
     "//third_party/opus",
   ]
diff --git a/starboard/android/shared/android_main.cc b/starboard/android/shared/android_main.cc
index 0ed8090673aa..1a42ab2c65e2 100644
--- a/starboard/android/shared/android_main.cc
+++ b/starboard/android/shared/android_main.cc
@@ -18,11 +18,11 @@
 #include <unistd.h>
 #include <atomic>
 
-// #include "game-activity/GameActivity.h"
 #include "starboard/android/shared/application_android.h"
 #include "starboard/android/shared/jni_env_ext.h"
 #include "starboard/android/shared/jni_utils.h"
 #include "starboard/android/shared/log_internal.h"
+#include "starboard/android/shared/starboard_bridge.h"
 #include "starboard/common/file.h"
 #include "starboard/common/semaphore.h"
 #include "starboard/common/string.h"
@@ -30,6 +30,7 @@
 #include "starboard/event.h"
 #include "starboard/log.h"
 #include "starboard/shared/starboard/command_line.h"
+#include "starboard/shared/starboard/log_mutex.h"
 #include "starboard/thread.h"
 #if SB_IS(EVERGREEN_COMPATIBLE)
 #include "starboard/crashpad_wrapper/wrapper.h"  // nogncheck
@@ -61,40 +62,14 @@ std::atomic_bool g_app_running{false};
 std::vector<std::string> GetArgs() {
   std::vector<std::string> args;
   // Fake program name as args[0]
-  args.push_back(strdup("android_main"));
+  args.push_back("android_main");
 
-  JniEnvExt* env = JniEnvExt::Get();
-
-  ScopedLocalJavaRef<jobjectArray> args_array(
-      env->CallStarboardObjectMethodOrAbort("getArgs",
-                                            "()[Ljava/lang/String;"));
-  jint argc = !args_array ? 0 : env->GetArrayLength(args_array.Get());
-
-  for (jint i = 0; i < argc; i++) {
-    ScopedLocalJavaRef<jstring> element(
-        env->GetObjectArrayElementOrAbort(args_array.Get(), i));
-    args.push_back(env->GetStringStandardUTFOrAbort(element.Get()));
-  }
+  JNIEnv* env = base::android::AttachCurrentThread();
+  StarboardBridge::GetInstance()->AppendArgs(env, &args);
 
   return args;
 }
 
-std::string GetStartDeepLink() {
-  JniEnvExt* env = JniEnvExt::Get();
-  std::string start_url;
-
-  ScopedLocalJavaRef<jstring> j_url(env->CallStarboardObjectMethodOrAbort(
-      "getStartDeepLink", "()Ljava/lang/String;"));
-  if (j_url) {
-    auto j_url_str = j_url.Get();
-    if (env->GetStringLength(j_url_str) != 0) {
-      start_url = env->GetStringStandardUTFOrAbort(j_url_str);
-    }
-  }
-  SB_LOG(INFO) << "GetStartDeepLink: " << start_url;
-  return start_url;
-}
-
 #if SB_IS(EVERGREEN_COMPATIBLE)
 bool CopyDirContents(const std::string& src_dir_path,
                      const std::string& dst_dir_path) {
@@ -252,9 +227,8 @@ void* ThreadEntryPoint(void* context) {
 
   // Inform StarboardBridge that the run loop has exited so it can cleanup and
   // kill the process.
-  JniEnvExt* env = JniEnvExt::Get();
-  env->CallStarboardVoidMethodOrAbort("afterStopped", "()V");
-
+  JNIEnv* env = base::android::AttachCurrentThread();
+  StarboardBridge::GetInstance()->AfterStopped(env);
   return NULL;
 }
 #endif  // SB_IS(EVERGREEN_COMPATIBLE)
@@ -292,10 +266,16 @@ void StarboardThreadLaunch() {
 }
 #endif  // SB_IS(EVERGREEN_COMPATIBLE)
 
+// TODO(cobalt, b/372559388): consolidate this function when fully deprecate
+// JniEnvExt.
 extern "C" SB_EXPORT_PLATFORM void Java_dev_cobalt_coat_StarboardBridge_initJNI(
     JniEnvExt* env,
     jobject starboard_bridge) {
   JniEnvExt::Initialize(env, starboard_bridge);
+
+  // Initialize the singleton instance of StarboardBridge
+  JNIEnv* jni_env = base::android::AttachCurrentThread();
+  StarboardBridge::GetInstance()->Initialize(jni_env, starboard_bridge);
 }
 
 extern "C" SB_EXPORT_PLATFORM jlong
@@ -303,6 +283,7 @@ Java_dev_cobalt_coat_StarboardBridge_startNativeStarboard(JniEnvExt* env) {
 #if SB_IS(EVERGREEN_COMPATIBLE)
   StarboardThreadLaunch();
 #else
+  starboard::shared::starboard::GetLoggingMutex();
   auto command_line = std::make_unique<CommandLine>(GetArgs());
   LogInit(*command_line);
   auto* nativeApp = new ApplicationAndroid(std::move(command_line));
@@ -372,8 +353,10 @@ extern "C" int SbRunStarboardMain(int argc,
   g_app_created_semaphore->Put();
 
   // Enter the Starboard run loop until stopped.
-  int error_level =
-      app.Run(std::move(command_line), GetStartDeepLink().c_str());
+  JNIEnv* env = base::android::AttachCurrentThread();
+  std::string start_url = StarboardBridge::GetInstance()->GetStartDeepLink(env);
+  SB_LOG(INFO) << "GetStartDeepLink: " << start_url;
+  int error_level = app.Run(std::move(command_line), start_url.c_str());
 
   // Mark the app not running before informing StarboardBridge that the app is
   // stopped so that we won't send any more AndroidCommands as a result of
diff --git a/starboard/android/shared/application_android.cc b/starboard/android/shared/application_android.cc
index 5d076a7f2688..1e29cb0a075d 100644
--- a/starboard/android/shared/application_android.cc
+++ b/starboard/android/shared/application_android.cc
@@ -24,6 +24,7 @@
 #include <string>
 #include <vector>
 
+#include "base/android/jni_android.h"
 #include "starboard/extension/accessibility.h"
 
 #include "starboard/android/shared/file_internal.h"
@@ -44,14 +45,6 @@
 namespace starboard {
 namespace android {
 namespace shared {
-namespace {
-int64_t GetAppStartTimestamp() {
-  JniEnvExt* env = JniEnvExt::Get();
-  jlong app_start_timestamp =
-      env->CallStarboardLongMethodOrAbort("getAppStartTimestamp", "()J");
-  return app_start_timestamp;
-}
-}  // namespace
 
 // TODO(cobalt, b/378708359): Remove this dummy init.
 void stubSbEventHandle(const SbEvent* event) {
@@ -74,14 +67,18 @@ ApplicationAndroid::ApplicationAndroid(
   jobject local_ref = env->CallStarboardObjectMethodOrAbort(
       "getResourceOverlay", "()Ldev/cobalt/coat/ResourceOverlay;");
   resource_overlay_ = env->ConvertLocalRefToGlobalRef(local_ref);
-  SbAudioSinkPrivate::Initialize();
-  app_start_timestamp_ = GetAppStartTimestamp();
-  env->CallStarboardVoidMethodOrAbort("applicationStarted", "()V");
+
+  ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl::Initialize();
+
+  JNIEnv* jni_env = base::android::AttachCurrentThread();
+  app_start_timestamp_ = starboard_bridge_->GetAppStartTimestamp(jni_env);
+
+  starboard_bridge_->ApplicationStarted(jni_env);
 }
 
 ApplicationAndroid::~ApplicationAndroid() {
-  JniEnvExt* env = JniEnvExt::Get();
-  env->CallStarboardVoidMethodOrAbort("applicationStopping", "()V");
+  JNIEnv* env = base::android::AttachCurrentThread();
+  starboard_bridge_->ApplicationStopping(env);
 
   // The application is exiting.
   // Release the global reference.
@@ -94,12 +91,6 @@ ApplicationAndroid::~ApplicationAndroid() {
   JniEnvExt::OnThreadShutdown();
 }
 
-extern "C" SB_EXPORT_PLATFORM void
-Java_dev_cobalt_coat_StarboardBridge_nativeOnStop(JniEnvExt* env) {
-  SbAudioSinkPrivate::TearDown();
-  SbFileAndroidTeardown();
-}
-
 extern "C" SB_EXPORT_PLATFORM jboolean
 Java_dev_cobalt_coat_StarboardBridge_nativeOnSearchRequested(
     JniEnvExt* env,
@@ -108,14 +99,6 @@ Java_dev_cobalt_coat_StarboardBridge_nativeOnSearchRequested(
   return true;
 }
 
-extern "C" SB_EXPORT_PLATFORM jlong
-Java_dev_cobalt_coat_StarboardBridge_nativeCurrentMonotonicTime(
-    JNIEnv* env,
-    jobject jcaller,
-    jboolean online) {
-  return CurrentMonotonicTime();
-}
-
 extern "C" SB_EXPORT_PLATFORM void
 Java_dev_cobalt_coat_CobaltSystemConfigChangeReceiver_nativeDateTimeConfigurationChanged(
     JNIEnv* env,
diff --git a/starboard/android/shared/application_android.h b/starboard/android/shared/application_android.h
index 16c2a577840a..abf11b6734f7 100644
--- a/starboard/android/shared/application_android.h
+++ b/starboard/android/shared/application_android.h
@@ -20,7 +20,7 @@
 #include <string>
 #include <unordered_map>
 
-#include "starboard/android/shared/jni_env_ext.h"
+#include "starboard/android/shared/starboard_bridge.h"
 #include "starboard/common/log.h"
 #include "starboard/common/mutex.h"
 #include "starboard/shared/internal_only.h"
@@ -66,6 +66,10 @@ class ApplicationAndroid
   void WakeSystemEventWait() override {}
 
  private:
+  // starboard_bridge_ is a global singleton, use a raw pointer to not interfere
+  // with it's lifecycle management.
+  const raw_ptr<StarboardBridge> starboard_bridge_ =
+      StarboardBridge::GetInstance();
   jobject resource_overlay_;
 
   Mutex overlay_mutex_;
diff --git a/starboard/android/shared/audio_track_audio_sink_type.cc b/starboard/android/shared/audio_track_audio_sink_type.cc
index 4af3a1751f18..cb7845c1fae4 100644
--- a/starboard/android/shared/audio_track_audio_sink_type.cc
+++ b/starboard/android/shared/audio_track_audio_sink_type.cc
@@ -561,20 +561,30 @@ int AudioTrackAudioSinkType::GetMinBufferSizeInFramesInternal(
 }  // namespace android
 }  // namespace starboard
 
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace audio_sink {
+
 // static
-void SbAudioSinkPrivate::PlatformInitialize() {
+void SbAudioSinkImpl::PlatformInitialize() {
   SB_DCHECK(!audio_track_audio_sink_type_);
   audio_track_audio_sink_type_ =
-      new starboard::android::shared::AudioTrackAudioSinkType;
+      new ::starboard::android::shared::AudioTrackAudioSinkType;
   SetPrimaryType(audio_track_audio_sink_type_);
   EnableFallbackToStub();
   audio_track_audio_sink_type_->TestMinRequiredFrames();
 }
 
 // static
-void SbAudioSinkPrivate::PlatformTearDown() {
+void SbAudioSinkImpl::PlatformTearDown() {
   SB_DCHECK(audio_track_audio_sink_type_ == GetPrimaryType());
   SetPrimaryType(NULL);
   delete audio_track_audio_sink_type_;
   audio_track_audio_sink_type_ = NULL;
 }
+
+}  // namespace audio_sink
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/android/shared/audio_track_audio_sink_type.h b/starboard/android/shared/audio_track_audio_sink_type.h
index 9d59c8049e92..700f421094ed 100644
--- a/starboard/android/shared/audio_track_audio_sink_type.h
+++ b/starboard/android/shared/audio_track_audio_sink_type.h
@@ -100,7 +100,8 @@ class AudioTrackAudioSinkType : public SbAudioSinkPrivate::Type {
   bool has_remote_audio_output_ = false;
 };
 
-class AudioTrackAudioSink : public SbAudioSinkPrivate {
+class AudioTrackAudioSink
+    : public ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl {
  public:
   AudioTrackAudioSink(
       Type* type,
diff --git a/starboard/android/shared/media_capabilities_cache.cc b/starboard/android/shared/media_capabilities_cache.cc
index 10e2d1998d84..436eed009bba 100644
--- a/starboard/android/shared/media_capabilities_cache.cc
+++ b/starboard/android/shared/media_capabilities_cache.cc
@@ -18,6 +18,7 @@
 
 #include "starboard/android/shared/jni_utils.h"
 #include "starboard/android/shared/media_common.h"
+#include "starboard/android/shared/starboard_bridge.h"
 #include "starboard/common/log.h"
 #include "starboard/common/once.h"
 #include "starboard/shared/starboard/media/key_system_supportability_cache.h"
@@ -188,9 +189,9 @@ bool GetIsCbcsSupported() {
 std::set<SbMediaTransferId> GetSupportedHdrTypes() {
   std::set<SbMediaTransferId> supported_transfer_ids;
 
-  JniEnvExt* env = JniEnvExt::Get();
-  jintArray j_supported_hdr_types = static_cast<jintArray>(
-      env->CallStarboardObjectMethodOrAbort("getSupportedHdrTypes", "()[I"));
+  JNIEnv* env = base::android::AttachCurrentThread();
+  base::android::ScopedJavaLocalRef<jintArray> j_supported_hdr_types =
+      StarboardBridge::GetInstance()->GetSupportedHdrTypes(env);
 
   if (!j_supported_hdr_types) {
     // Failed to get supported hdr types.
@@ -198,8 +199,9 @@ std::set<SbMediaTransferId> GetSupportedHdrTypes() {
     return std::set<SbMediaTransferId>();
   }
 
-  jsize length = env->GetArrayLength(j_supported_hdr_types);
-  jint* numbers = env->GetIntArrayElements(j_supported_hdr_types, 0);
+  jsize length = env->GetArrayLength(j_supported_hdr_types.obj());
+  jint* numbers =
+      env->GetIntArrayElements(j_supported_hdr_types.obj(), nullptr);
   for (int i = 0; i < length; i++) {
     switch (numbers[i]) {
       case HDR_TYPE_DOLBY_VISION:
@@ -214,7 +216,7 @@ std::set<SbMediaTransferId> GetSupportedHdrTypes() {
         continue;
     }
   }
-  env->ReleaseIntArrayElements(j_supported_hdr_types, numbers, 0);
+  env->ReleaseIntArrayElements(j_supported_hdr_types.obj(), numbers, 0);
 
   return supported_transfer_ids;
 }
diff --git a/starboard/android/shared/media_is_audio_supported.cc b/starboard/android/shared/media_is_audio_supported.cc
index 023cbfc5f8fb..01f2e6638fca 100644
--- a/starboard/android/shared/media_is_audio_supported.cc
+++ b/starboard/android/shared/media_is_audio_supported.cc
@@ -22,13 +22,17 @@
 #include "starboard/configuration_constants.h"
 #include "starboard/media.h"
 
-using starboard::android::shared::MediaCapabilitiesCache;
-using starboard::android::shared::SupportedAudioCodecToMimeType;
-using starboard::shared::starboard::media::MimeType;
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
 
-bool SbMediaIsAudioSupported(SbMediaAudioCodec audio_codec,
-                             const MimeType* mime_type,
-                             int64_t bitrate) {
+using ::starboard::android::shared::MediaCapabilitiesCache;
+using ::starboard::android::shared::SupportedAudioCodecToMimeType;
+
+bool MediaIsAudioSupported(SbMediaAudioCodec audio_codec,
+                           const MimeType* mime_type,
+                           int64_t bitrate) {
   if (bitrate >= kSbMediaMaxAudioBitrateInBitsPerSecond) {
     return false;
   }
@@ -80,3 +84,8 @@ bool SbMediaIsAudioSupported(SbMediaAudioCodec audio_codec,
   return MediaCapabilitiesCache::GetInstance()->IsPassthroughSupported(
       audio_codec);
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/android/shared/media_is_supported.cc b/starboard/android/shared/media_is_supported.cc
index 04acefb035b1..f68de335d6e3 100644
--- a/starboard/android/shared/media_is_supported.cc
+++ b/starboard/android/shared/media_is_supported.cc
@@ -21,13 +21,17 @@
 #include "starboard/media.h"
 #include "starboard/shared/starboard/media/mime_type.h"
 
-bool SbMediaIsSupported(SbMediaVideoCodec video_codec,
-                        SbMediaAudioCodec audio_codec,
-                        const char* key_system) {
-  using starboard::android::shared::IsWidevineL1;
-  using starboard::android::shared::IsWidevineL3;
-  using starboard::android::shared::MediaCapabilitiesCache;
-  using starboard::shared::starboard::media::MimeType;
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
+
+bool MediaIsSupported(SbMediaVideoCodec video_codec,
+                      SbMediaAudioCodec audio_codec,
+                      const char* key_system) {
+  using ::starboard::android::shared::IsWidevineL1;
+  using ::starboard::android::shared::IsWidevineL3;
+  using ::starboard::android::shared::MediaCapabilitiesCache;
 
   // It is possible that the |key_system| comes with extra attributes, like
   // `com.widevine.alpha; encryptionscheme="cenc"`. We prepend "key_system/"
@@ -64,3 +68,8 @@ bool SbMediaIsSupported(SbMediaVideoCodec video_codec,
 
   return true;
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/android/shared/media_is_video_supported.cc b/starboard/android/shared/media_is_video_supported.cc
index cee2457b3a66..4b33f7a40c5e 100644
--- a/starboard/android/shared/media_is_video_supported.cc
+++ b/starboard/android/shared/media_is_video_supported.cc
@@ -21,25 +21,28 @@
 #include "starboard/media.h"
 #include "starboard/shared/starboard/media/media_util.h"
 
-using starboard::android::shared::MaxMediaCodecOutputBuffersLookupTable;
-using starboard::android::shared::MediaCapabilitiesCache;
-using starboard::android::shared::SupportedVideoCodecToMimeType;
-using starboard::shared::starboard::media::IsSDRVideo;
-using starboard::shared::starboard::media::MimeType;
-
-bool SbMediaIsVideoSupported(SbMediaVideoCodec video_codec,
-                             const MimeType* mime_type,
-                             int profile,
-                             int level,
-                             int bit_depth,
-                             SbMediaPrimaryId primary_id,
-                             SbMediaTransferId transfer_id,
-                             SbMediaMatrixId matrix_id,
-                             int frame_width,
-                             int frame_height,
-                             int64_t bitrate,
-                             int fps,
-                             bool decode_to_texture_required) {
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
+
+using ::starboard::android::shared::MaxMediaCodecOutputBuffersLookupTable;
+using ::starboard::android::shared::MediaCapabilitiesCache;
+using ::starboard::android::shared::SupportedVideoCodecToMimeType;
+
+bool MediaIsVideoSupported(SbMediaVideoCodec video_codec,
+                           const MimeType* mime_type,
+                           int profile,
+                           int level,
+                           int bit_depth,
+                           SbMediaPrimaryId primary_id,
+                           SbMediaTransferId transfer_id,
+                           SbMediaMatrixId matrix_id,
+                           int frame_width,
+                           int frame_height,
+                           int64_t bitrate,
+                           int fps,
+                           bool decode_to_texture_required) {
   const bool must_support_hdr =
       !IsSDRVideo(bit_depth, primary_id, transfer_id, matrix_id);
   if (must_support_hdr &&
@@ -115,3 +118,8 @@ bool SbMediaIsVideoSupported(SbMediaVideoCodec video_codec,
       mime, require_secure_playback, must_support_hdr, must_support_tunnel_mode,
       frame_width, frame_height, bitrate, fps);
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/android/shared/player_components_factory.h b/starboard/android/shared/player_components_factory.h
index 469fd669746b..d17e7489a6e0 100644
--- a/starboard/android/shared/player_components_factory.h
+++ b/starboard/android/shared/player_components_factory.h
@@ -99,7 +99,8 @@ class AudioRendererSinkAndroid : public ::starboard::shared::starboard::player::
                 SbAudioSinkPrivate::ErrorFunc error_func,
                 void* context) {
               auto type = static_cast<AudioTrackAudioSinkType*>(
-                  SbAudioSinkPrivate::GetPreferredType());
+                  ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl::
+                      GetPreferredType());
 
               return type->Create(
                   channels, sampling_frequency_hz, audio_sample_type,
diff --git a/starboard/android/shared/starboard_bridge.cc b/starboard/android/shared/starboard_bridge.cc
new file mode 100644
index 000000000000..b53eca201e40
--- /dev/null
+++ b/starboard/android/shared/starboard_bridge.cc
@@ -0,0 +1,99 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "starboard/android/shared/starboard_bridge.h"
+
+#include "starboard/android/shared/file_internal.h"
+#include "starboard/common/time.h"
+#include "starboard/media.h"
+#include "starboard/shared/starboard/audio_sink/audio_sink_internal.h"
+
+// Must come after all headers that specialize FromJniType() / ToJniType().
+#include "base/android/jni_array.h"
+#include "base/android/jni_string.h"
+#include "cobalt/android/jni_headers/StarboardBridge_jni.h"
+
+namespace starboard {
+namespace android {
+namespace shared {
+
+extern "C" SB_EXPORT_PLATFORM void JNI_StarboardBridge_OnStop(JNIEnv* env) {
+  ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl::TearDown();
+  SbFileAndroidTeardown();
+}
+
+extern "C" SB_EXPORT_PLATFORM jlong
+JNI_StarboardBridge_CurrentMonotonicTime(JNIEnv* env) {
+  return CurrentMonotonicTime();
+}
+
+// StarboardBridge::GetInstance() should not be inlined in the
+// header. This makes sure that when source files from multiple targets include
+// this header they don't end up with different copies of the inlined code
+// creating multiple copies of the singleton.
+// static
+StarboardBridge* StarboardBridge::GetInstance() {
+  return base::Singleton<StarboardBridge>::get();
+}
+
+void StarboardBridge::Initialize(JNIEnv* env, jobject obj) {
+  j_starboard_bridge_.Reset(env, obj);
+}
+
+long StarboardBridge::GetAppStartTimestamp(JNIEnv* env) {
+  CHECK(env);
+  return Java_StarboardBridge_getAppStartTimestamp(env, j_starboard_bridge_);
+}
+
+void StarboardBridge::ApplicationStarted(JNIEnv* env) {
+  CHECK(env);
+  Java_StarboardBridge_applicationStarted(env, j_starboard_bridge_);
+}
+
+void StarboardBridge::ApplicationStopping(JNIEnv* env) {
+  CHECK(env);
+  Java_StarboardBridge_applicationStopping(env, j_starboard_bridge_);
+}
+
+void StarboardBridge::AfterStopped(JNIEnv* env) {
+  CHECK(env);
+  Java_StarboardBridge_afterStopped(env, j_starboard_bridge_);
+}
+
+void StarboardBridge::AppendArgs(JNIEnv* env,
+                                 std::vector<std::string>* args_vector) {
+  CHECK(env);
+  base::android::ScopedJavaLocalRef<jobjectArray> args_java =
+      Java_StarboardBridge_getArgs(env, j_starboard_bridge_);
+  base::android::AppendJavaStringArrayToStringVector(env, args_java,
+                                                     args_vector);
+}
+
+std::string StarboardBridge::GetStartDeepLink(JNIEnv* env) {
+  CHECK(env);
+  base::android::ScopedJavaLocalRef<jstring> start_deep_link_java =
+      Java_StarboardBridge_getStartDeepLink(env, j_starboard_bridge_);
+  std::string start_deep_link =
+      base::android::ConvertJavaStringToUTF8(env, start_deep_link_java);
+  return start_deep_link;
+}
+
+base::android::ScopedJavaLocalRef<jintArray>
+StarboardBridge::GetSupportedHdrTypes(JNIEnv* env) {
+  CHECK(env);
+  return Java_StarboardBridge_getSupportedHdrTypes(env, j_starboard_bridge_);
+}
+}  // namespace shared
+}  // namespace android
+}  // namespace starboard
diff --git a/starboard/android/shared/starboard_bridge.h b/starboard/android/shared/starboard_bridge.h
new file mode 100644
index 000000000000..d834c3b20543
--- /dev/null
+++ b/starboard/android/shared/starboard_bridge.h
@@ -0,0 +1,70 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef STARBOARD_ANDROID_SHARED_STARBOARD_BRIDGE_H_
+#define STARBOARD_ANDROID_SHARED_STARBOARD_BRIDGE_H_
+
+#include <jni.h>
+
+#include "base/android/jni_android.h"
+#include "base/android/scoped_java_ref.h"
+#include "base/memory/singleton.h"
+
+namespace starboard {
+namespace android {
+namespace shared {
+
+// This class serves as a bridge between the native code and Android
+// StarboardBridge Java class.
+class StarboardBridge {
+ public:
+  // Returns the singleton.
+  static StarboardBridge* GetInstance();
+
+  void Initialize(JNIEnv* env, jobject obj);
+
+  long GetAppStartTimestamp(JNIEnv* env);
+
+  void ApplicationStarted(JNIEnv* env);
+
+  void ApplicationStopping(JNIEnv* env);
+
+  void AfterStopped(JNIEnv* env);
+
+  void AppendArgs(JNIEnv* env, std::vector<std::string>* args_vector);
+
+  std::string GetStartDeepLink(JNIEnv* env);
+
+  base::android::ScopedJavaLocalRef<jintArray> GetSupportedHdrTypes(
+      JNIEnv* env);
+
+ private:
+  StarboardBridge() = default;
+  ~StarboardBridge() = default;
+
+  // Prevent copy construction and assignment
+  StarboardBridge(const StarboardBridge&) = delete;
+  StarboardBridge& operator=(const StarboardBridge&) = delete;
+
+  friend struct base::DefaultSingletonTraits<StarboardBridge>;
+
+  // Java StarboardBridge instance.
+  base::android::ScopedJavaGlobalRef<jobject> j_starboard_bridge_;
+};
+
+}  // namespace shared
+}  // namespace android
+}  // namespace starboard
+
+#endif  // STARBOARD_ANDROID_SHARED_STARBOARD_BRIDGE_H_
diff --git a/starboard/android/x86/platform_configuration/configuration.gni b/starboard/android/x86/platform_configuration/configuration.gni
index 7b1100758777..3754e8c889b8 100644
--- a/starboard/android/x86/platform_configuration/configuration.gni
+++ b/starboard/android/x86/platform_configuration/configuration.gni
@@ -14,7 +14,6 @@
 
 import("//starboard/android/shared/platform_configuration/configuration.gni")
 
-android_abi = "x86"
 sabi_path = "//starboard/sabi/x86/sabi-v$sb_api_version.json"
 
 sb_enable_opus_sse = false
diff --git a/starboard/linux/shared/audio_sink_type_dispatcher.cc b/starboard/linux/shared/audio_sink_type_dispatcher.cc
index 2a0b5817f93a..4d956205125c 100644
--- a/starboard/linux/shared/audio_sink_type_dispatcher.cc
+++ b/starboard/linux/shared/audio_sink_type_dispatcher.cc
@@ -17,28 +17,38 @@
 #include "starboard/shared/pulse/pulse_audio_sink_type.h"
 #include "starboard/shared/starboard/audio_sink/audio_sink_internal.h"
 
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace audio_sink {
 namespace {
 bool is_fallback_to_alsa = false;
-}
+}  // namespace
 
 // static
-void SbAudioSinkPrivate::PlatformInitialize() {
-  starboard::shared::pulse::PlatformInitialize();
+void SbAudioSinkImpl::PlatformInitialize() {
+  ::starboard::shared::pulse::PlatformInitialize();
   if (GetPrimaryType()) {
     SB_LOG(INFO) << "Use PulseAudio";
   } else {
     SB_LOG(INFO) << "Use ALSA";
-    starboard::shared::alsa::PlatformInitialize();
+    ::starboard::shared::alsa::PlatformInitialize();
     is_fallback_to_alsa = true;
   }
-  SbAudioSinkPrivate::EnableFallbackToStub();
+  ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl::
+      EnableFallbackToStub();
 }
 
 // static
-void SbAudioSinkPrivate::PlatformTearDown() {
+void SbAudioSinkImpl::PlatformTearDown() {
   if (is_fallback_to_alsa) {
-    starboard::shared::alsa::PlatformTearDown();
+    ::starboard::shared::alsa::PlatformTearDown();
   } else {
-    starboard::shared::pulse::PlatformTearDown();
+    ::starboard::shared::pulse::PlatformTearDown();
   }
 }
+
+}  // namespace audio_sink
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/linux/shared/media_is_audio_supported.cc b/starboard/linux/shared/media_is_audio_supported.cc
index ce2fbdff69a1..6b77bb0eeb3f 100644
--- a/starboard/linux/shared/media_is_audio_supported.cc
+++ b/starboard/linux/shared/media_is_audio_supported.cc
@@ -19,11 +19,14 @@
 #include "starboard/configuration_constants.h"
 #include "starboard/media.h"
 
-using ::starboard::shared::starboard::media::MimeType;
-
-bool SbMediaIsAudioSupported(SbMediaAudioCodec audio_codec,
-                             const MimeType* mime_type,
-                             int64_t bitrate) {
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
+
+bool MediaIsAudioSupported(SbMediaAudioCodec audio_codec,
+                           const MimeType* mime_type,
+                           int64_t bitrate) {
   if (audio_codec == kSbMediaAudioCodecAac) {
     return bitrate <= kSbMediaMaxAudioBitrateInBitsPerSecond;
   }
@@ -52,3 +55,8 @@ bool SbMediaIsAudioSupported(SbMediaAudioCodec audio_codec,
 
   return false;
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/linux/shared/media_is_video_supported.cc b/starboard/linux/shared/media_is_video_supported.cc
index e932cb17f9b7..3fb39910b0de 100644
--- a/starboard/linux/shared/media_is_video_supported.cc
+++ b/starboard/linux/shared/media_is_video_supported.cc
@@ -22,23 +22,26 @@
 #include "starboard/shared/libde265/de265_library_loader.h"
 #include "starboard/shared/starboard/media/media_util.h"
 
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
+
 using ::starboard::shared::de265::is_de265_supported;
-using ::starboard::shared::starboard::media::IsSDRVideo;
-using ::starboard::shared::starboard::media::MimeType;
 
-bool SbMediaIsVideoSupported(SbMediaVideoCodec video_codec,
-                             const MimeType* mime_type,
-                             int profile,
-                             int level,
-                             int bit_depth,
-                             SbMediaPrimaryId primary_id,
-                             SbMediaTransferId transfer_id,
-                             SbMediaMatrixId matrix_id,
-                             int frame_width,
-                             int frame_height,
-                             int64_t bitrate,
-                             int fps,
-                             bool decode_to_texture_required) {
+bool MediaIsVideoSupported(SbMediaVideoCodec video_codec,
+                           const MimeType* mime_type,
+                           int profile,
+                           int level,
+                           int bit_depth,
+                           SbMediaPrimaryId primary_id,
+                           SbMediaTransferId transfer_id,
+                           SbMediaMatrixId matrix_id,
+                           int frame_width,
+                           int frame_height,
+                           int64_t bitrate,
+                           int fps,
+                           bool decode_to_texture_required) {
   if (!IsSDRVideo(bit_depth, primary_id, transfer_id, matrix_id)) {
     if (bit_depth != 10 && bit_depth != 12) {
       return false;
@@ -68,3 +71,8 @@ bool SbMediaIsVideoSupported(SbMediaVideoCodec video_codec,
          frame_width <= 1920 && frame_height <= 1080 &&
          bitrate <= kSbMediaMaxVideoBitrateInBitsPerSecond && fps <= 60;
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/nplb/BUILD.gn b/starboard/nplb/BUILD.gn
index a6c3b9e0a2ec..6910b4e02555 100644
--- a/starboard/nplb/BUILD.gn
+++ b/starboard/nplb/BUILD.gn
@@ -47,6 +47,8 @@ test("nplb") {
     "//starboard/nplb/sabi/struct_alignment_test.cc",
     "//starboard/shared/starboard/drm/drm_test_helpers.cc",
     "//starboard/shared/starboard/drm/drm_test_helpers.h",
+    "//starboard/testing/fake_graphics_context_provider.cc",
+    "//starboard/testing/fake_graphics_context_provider.h",
     "align_test.cc",
     "audio_sink_create_test.cc",
     "audio_sink_destroy_test.cc",
@@ -219,8 +221,6 @@ test("nplb") {
 
   if (!is_android) {
     sources += [
-      "//starboard/testing/fake_graphics_context_provider.cc",
-      "//starboard/testing/fake_graphics_context_provider.h",
       "maximum_player_configuration_explorer_test.cc",
       "media_set_audio_write_duration_test.cc",
       "multiple_player_test.cc",
diff --git a/starboard/nplb/maximum_player_configuration_explorer.h b/starboard/nplb/maximum_player_configuration_explorer.h
index 80ddf7b34bc2..bf74aea0309c 100644
--- a/starboard/nplb/maximum_player_configuration_explorer.h
+++ b/starboard/nplb/maximum_player_configuration_explorer.h
@@ -23,8 +23,7 @@
 #include "starboard/nplb/player_test_util.h"
 #include "starboard/player.h"
 #include "starboard/shared/starboard/media/media_util.h"
-// TODO(cobalt, b/377295011): remove the nogncheck annotation.
-#include "starboard/testing/fake_graphics_context_provider.h"  // nogncheck
+#include "starboard/testing/fake_graphics_context_provider.h"
 
 namespace starboard {
 namespace nplb {
diff --git a/starboard/nplb/player_test_util.cc b/starboard/nplb/player_test_util.cc
index 01bfd49c6830..ec9bf4ac6016 100644
--- a/starboard/nplb/player_test_util.cc
+++ b/starboard/nplb/player_test_util.cc
@@ -24,8 +24,6 @@
 #include "starboard/nplb/maximum_player_configuration_explorer.h"
 #include "starboard/nplb/player_creation_param_helpers.h"
 #include "starboard/shared/starboard/player/video_dmp_reader.h"
-// TODO(cobalt, b/377295011): remove the nogncheck annotation.
-#include "starboard/testing/fake_graphics_context_provider.h"  // nogncheck
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace starboard {
@@ -40,7 +38,6 @@ using std::placeholders::_1;
 using std::placeholders::_2;
 using std::placeholders::_3;
 using std::placeholders::_4;
-using testing::FakeGraphicsContextProvider;
 
 const char* kAudioTestFiles[] = {
     "beneath_the_canopy_aac_stereo.dmp",
diff --git a/starboard/raspi/shared/application_dispmanx.cc b/starboard/raspi/shared/application_dispmanx.cc
index ef924b0e92b5..a5987c21664e 100644
--- a/starboard/raspi/shared/application_dispmanx.cc
+++ b/starboard/raspi/shared/application_dispmanx.cc
@@ -68,12 +68,12 @@ bool ApplicationDispmanx::DestroyWindow(SbWindow window) {
 }
 
 void ApplicationDispmanx::Initialize() {
-  SbAudioSinkPrivate::Initialize();
+  ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl::Initialize();
 }
 
 void ApplicationDispmanx::Teardown() {
   ShutdownDispmanx();
-  SbAudioSinkPrivate::TearDown();
+  ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl::TearDown();
 }
 
 void ApplicationDispmanx ::OnSuspend() {
diff --git a/starboard/raspi/shared/audio_sink_type_dispatcher.cc b/starboard/raspi/shared/audio_sink_type_dispatcher.cc
index 97b918d0f794..70a8d746154f 100644
--- a/starboard/raspi/shared/audio_sink_type_dispatcher.cc
+++ b/starboard/raspi/shared/audio_sink_type_dispatcher.cc
@@ -15,13 +15,23 @@
 #include "starboard/shared/alsa/alsa_audio_sink_type.h"
 #include "starboard/shared/starboard/audio_sink/audio_sink_internal.h"
 
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace audio_sink {
+
 // static
-void SbAudioSinkPrivate::PlatformInitialize() {
-  starboard::shared::alsa::PlatformInitialize();
+void SbAudioSinkImpl::PlatformInitialize() {
+  ::starboard::shared::alsa::PlatformInitialize();
   SbAudioSinkPrivate::EnableFallbackToStub();
 }
 
 // static
-void SbAudioSinkPrivate::PlatformTearDown() {
-  starboard::shared::alsa::PlatformTearDown();
+void SbAudioSinkImpl::PlatformTearDown() {
+  ::starboard::shared::alsa::PlatformTearDown();
 }
+
+}  // namespace audio_sink
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/raspi/shared/media_is_video_supported.cc b/starboard/raspi/shared/media_is_video_supported.cc
index 16a7088ed5f3..5e5da15b6626 100644
--- a/starboard/raspi/shared/media_is_video_supported.cc
+++ b/starboard/raspi/shared/media_is_video_supported.cc
@@ -19,22 +19,24 @@
 #include "starboard/media.h"
 #include "starboard/shared/starboard/media/media_util.h"
 
-using ::starboard::shared::starboard::media::IsSDRVideo;
-using ::starboard::shared::starboard::media::MimeType;
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
 
-bool SbMediaIsVideoSupported(SbMediaVideoCodec video_codec,
-                             const MimeType* mime_type,
-                             int profile,
-                             int level,
-                             int bit_depth,
-                             SbMediaPrimaryId primary_id,
-                             SbMediaTransferId transfer_id,
-                             SbMediaMatrixId matrix_id,
-                             int frame_width,
-                             int frame_height,
-                             int64_t bitrate,
-                             int fps,
-                             bool decode_to_texture_required) {
+bool MediaIsVideoSupported(SbMediaVideoCodec video_codec,
+                           const MimeType* mime_type,
+                           int profile,
+                           int level,
+                           int bit_depth,
+                           SbMediaPrimaryId primary_id,
+                           SbMediaTransferId transfer_id,
+                           SbMediaMatrixId matrix_id,
+                           int frame_width,
+                           int frame_height,
+                           int64_t bitrate,
+                           int fps,
+                           bool decode_to_texture_required) {
   if (!IsSDRVideo(bit_depth, primary_id, transfer_id, matrix_id)) {
     return false;
   }
@@ -46,3 +48,8 @@ bool SbMediaIsVideoSupported(SbMediaVideoCodec video_codec,
          frame_height <= 1080 &&
          bitrate <= kSbMediaMaxVideoBitrateInBitsPerSecond && fps <= 30;
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/shared/alsa/alsa_audio_sink_type.cc b/starboard/shared/alsa/alsa_audio_sink_type.cc
index 08bfd20bba30..8a683d943560 100644
--- a/starboard/shared/alsa/alsa_audio_sink_type.cc
+++ b/starboard/shared/alsa/alsa_audio_sink_type.cc
@@ -36,10 +36,11 @@ namespace shared {
 namespace alsa {
 namespace {
 
-using starboard::ScopedLock;
-using starboard::ScopedTryLock;
-using starboard::shared::alsa::AlsaGetBufferedFrames;
-using starboard::shared::alsa::AlsaWriteFrames;
+using ::starboard::ScopedLock;
+using ::starboard::ScopedTryLock;
+using ::starboard::shared::alsa::AlsaGetBufferedFrames;
+using ::starboard::shared::alsa::AlsaWriteFrames;
+using ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl;
 
 // The maximum number of frames that can be written to ALSA once.  It must be a
 // power of 2.  It is also used as the ALSA polling size.  A small number will
@@ -81,7 +82,7 @@ void* IncrementPointerByBytes(void* pointer, size_t offset) {
 // 2. It never stops the underlying ALSA audio sink once created.  When its
 //    source cannot provide enough data to continue playback, it simply writes
 //    silence to ALSA.
-class AlsaAudioSink : public SbAudioSinkPrivate {
+class AlsaAudioSink : public SbAudioSinkImpl {
  public:
   AlsaAudioSink(Type* type,
                 int channels,
@@ -142,8 +143,8 @@ class AlsaAudioSink : public SbAudioSinkPrivate {
   SbMediaAudioSampleType sample_type_;
 
   pthread_t audio_out_thread_;
-  starboard::Mutex mutex_;
-  starboard::ConditionVariable creation_signal_;
+  ::starboard::Mutex mutex_;
+  ::starboard::ConditionVariable creation_signal_;
 
   int64_t time_to_wait_;
 
@@ -215,7 +216,7 @@ AlsaAudioSink::~AlsaAudioSink() {
 // static
 void* AlsaAudioSink::ThreadEntryPoint(void* context) {
   pthread_setname_np(pthread_self(), "alsa_audio_out");
-  starboard::shared::pthread::ThreadSetPriority(kSbThreadPriorityRealTime);
+  ::starboard::shared::pthread::ThreadSetPriority(kSbThreadPriorityRealTime);
   SB_DCHECK(context);
   AlsaAudioSink* sink = reinterpret_cast<AlsaAudioSink*>(context);
   sink->AudioThreadFunc();
@@ -228,7 +229,7 @@ void AlsaAudioSink::AudioThreadFunc() {
       sample_type_ == kSbMediaAudioSampleTypeFloat32 ? SND_PCM_FORMAT_FLOAT_LE
                                                      : SND_PCM_FORMAT_S16;
 
-  playback_handle_ = starboard::shared::alsa::AlsaOpenPlaybackDevice(
+  playback_handle_ = ::starboard::shared::alsa::AlsaOpenPlaybackDevice(
       channels_, sampling_frequency_hz_, kFramesPerRequest,
       kALSABufferSizeInFrames, alsa_sample_type);
   {
@@ -249,7 +250,7 @@ void AlsaAudioSink::AudioThreadFunc() {
     }
   }
 
-  starboard::shared::alsa::AlsaCloseDevice(playback_handle_);
+  ::starboard::shared::alsa::AlsaCloseDevice(playback_handle_);
   ScopedLock lock(mutex_);
   playback_handle_ = NULL;
 }
@@ -450,25 +451,23 @@ SbAudioSink AlsaAudioSinkType::Create(
   return audio_sink;
 }
 
-}  // namespace
-
-namespace {
 AlsaAudioSinkType* alsa_audio_sink_type_;
+
 }  // namespace
 
 // static
 void PlatformInitialize() {
   SB_DCHECK(!alsa_audio_sink_type_);
   alsa_audio_sink_type_ = new AlsaAudioSinkType();
-  SbAudioSinkPrivate::SetPrimaryType(alsa_audio_sink_type_);
+  SbAudioSinkImpl::SetPrimaryType(alsa_audio_sink_type_);
 }
 
 // static
 void PlatformTearDown() {
   SB_DCHECK(alsa_audio_sink_type_);
-  SB_DCHECK(alsa_audio_sink_type_ == SbAudioSinkPrivate::GetPrimaryType());
+  SB_DCHECK(alsa_audio_sink_type_ == SbAudioSinkImpl::GetPrimaryType());
 
-  SbAudioSinkPrivate::SetPrimaryType(NULL);
+  SbAudioSinkImpl::SetPrimaryType(NULL);
   delete alsa_audio_sink_type_;
   alsa_audio_sink_type_ = NULL;
 }
diff --git a/starboard/shared/pulse/pulse_audio_sink_type.cc b/starboard/shared/pulse/pulse_audio_sink_type.cc
index eb091fc508e3..ccbcc83b0765 100644
--- a/starboard/shared/pulse/pulse_audio_sink_type.cc
+++ b/starboard/shared/pulse/pulse_audio_sink_type.cc
@@ -53,6 +53,7 @@ namespace pulse {
 namespace {
 
 using starboard::media::GetBytesPerSample;
+using ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl;
 
 const int64_t kAudioIdleSleepIntervalUsec = 15'000;    // 15ms
 const int64_t kAudioRunningSleepIntervalUsec = 5'000;  // 5ms
@@ -65,7 +66,7 @@ const size_t kPulseBufferSizeInFrames = 8192;
 
 class PulseAudioSinkType;
 
-class PulseAudioSink : public SbAudioSinkPrivate {
+class PulseAudioSink : public SbAudioSinkImpl {
  public:
   PulseAudioSink(PulseAudioSinkType* type,
                  int channels,
@@ -554,7 +555,7 @@ void PulseAudioSinkType::StateCallback(pa_context* context, void* userdata) {
 void* PulseAudioSinkType::ThreadEntryPoint(void* context) {
   pthread_setname_np(pthread_self(), "pulse_audio");
 
-  shared::pthread::ThreadSetPriority(kSbThreadPriorityRealTime);
+  ::starboard::shared::pthread::ThreadSetPriority(kSbThreadPriorityRealTime);
 
   SB_DCHECK(context);
   PulseAudioSinkType* type = static_cast<PulseAudioSinkType*>(context);
@@ -602,16 +603,16 @@ void PlatformInitialize() {
       std::unique_ptr<PulseAudioSinkType>(new PulseAudioSinkType());
   if (audio_sink_type->Initialize()) {
     pulse_audio_sink_type_ = audio_sink_type.release();
-    SbAudioSinkPrivate::SetPrimaryType(pulse_audio_sink_type_);
+    SbAudioSinkImpl::SetPrimaryType(pulse_audio_sink_type_);
   }
 }
 
 // static
 void PlatformTearDown() {
   SB_DCHECK(pulse_audio_sink_type_);
-  SB_DCHECK(pulse_audio_sink_type_ == SbAudioSinkPrivate::GetPrimaryType());
+  SB_DCHECK(pulse_audio_sink_type_ == SbAudioSinkImpl::GetPrimaryType());
 
-  SbAudioSinkPrivate::SetPrimaryType(NULL);
+  SbAudioSinkImpl::SetPrimaryType(NULL);
   delete pulse_audio_sink_type_;
   pulse_audio_sink_type_ = NULL;
   pulse_unload_library();
diff --git a/starboard/shared/starboard/audio_sink/audio_sink_create.cc b/starboard/shared/starboard/audio_sink/audio_sink_create.cc
index 7061745ff814..14867aa7e3e3 100644
--- a/starboard/shared/starboard/audio_sink/audio_sink_create.cc
+++ b/starboard/shared/starboard/audio_sink/audio_sink_create.cc
@@ -27,7 +27,7 @@ SbAudioSink SbAudioSinkCreate(
     SbAudioSinkUpdateSourceStatusFunc update_source_status_func,
     SbAudioSinkConsumeFramesFunc consume_frames_func,
     void* context) {
-  return SbAudioSinkPrivate::Create(
+  return ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl::Create(
       channels, sampling_frequency_hz, audio_sample_type,
       audio_frame_storage_type, frame_buffers, frame_buffers_size_in_frames,
       update_source_status_func, consume_frames_func, NULL /*error_func*/,
diff --git a/starboard/shared/starboard/audio_sink/audio_sink_destroy.cc b/starboard/shared/starboard/audio_sink/audio_sink_destroy.cc
index 4dea688d9606..ac0b1abd978b 100644
--- a/starboard/shared/starboard/audio_sink/audio_sink_destroy.cc
+++ b/starboard/shared/starboard/audio_sink/audio_sink_destroy.cc
@@ -18,16 +18,18 @@
 #include "starboard/shared/starboard/audio_sink/audio_sink_internal.h"
 
 void SbAudioSinkDestroy(SbAudioSink audio_sink) {
+  using ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl;
+
   if (audio_sink == kSbAudioSinkInvalid) {
     return;
   }
 
-  SbAudioSinkPrivate::Type* type = SbAudioSinkPrivate::GetPrimaryType();
+  SbAudioSinkPrivate::Type* type = SbAudioSinkImpl::GetPrimaryType();
   if (type && type->IsValid(audio_sink)) {
     type->Destroy(audio_sink);
     return;
   }
-  type = SbAudioSinkPrivate::GetFallbackType();
+  type = SbAudioSinkImpl::GetFallbackType();
   if (type && type->IsValid(audio_sink)) {
     type->Destroy(audio_sink);
     return;
diff --git a/starboard/shared/starboard/audio_sink/audio_sink_internal.cc b/starboard/shared/starboard/audio_sink/audio_sink_internal.cc
index 450c4186928a..5fb1ded88b85 100644
--- a/starboard/shared/starboard/audio_sink/audio_sink_internal.cc
+++ b/starboard/shared/starboard/audio_sink/audio_sink_internal.cc
@@ -21,6 +21,10 @@
 #include "starboard/shared/starboard/audio_sink/stub_audio_sink_type.h"
 #include "starboard/shared/starboard/command_line.h"
 
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace audio_sink {
 namespace {
 
 using std::placeholders::_1;
@@ -28,8 +32,8 @@ using std::placeholders::_2;
 using std::placeholders::_3;
 
 bool is_fallback_to_stub_enabled;
-SbAudioSinkPrivate::Type* primary_audio_sink_type;
-SbAudioSinkPrivate::Type* fallback_audio_sink_type;
+SbAudioSinkImpl::Type* primary_audio_sink_type;
+SbAudioSinkImpl::Type* fallback_audio_sink_type;
 
 // Command line switch that controls whether we default to the stub audio sink,
 // even when the primary audio sink may be available.
@@ -45,36 +49,34 @@ void WrapConsumeFramesFunc(SbAudioSinkConsumeFramesFunc sb_consume_frames_func,
 
 }  // namespace
 
-using starboard::shared::starboard::audio_sink::StubAudioSinkType;
-
 // static
-void SbAudioSinkPrivate::Initialize() {
+void SbAudioSinkImpl::Initialize() {
   fallback_audio_sink_type = new StubAudioSinkType;
   PlatformInitialize();
 }
 
 // static
-void SbAudioSinkPrivate::TearDown() {
+void SbAudioSinkImpl::TearDown() {
   PlatformTearDown();
   delete fallback_audio_sink_type;
   fallback_audio_sink_type = NULL;
 }
 
 // static
-void SbAudioSinkPrivate::SetPrimaryType(Type* type) {
+void SbAudioSinkImpl::SetPrimaryType(Type* type) {
   primary_audio_sink_type = type;
 }
 
 // static
-SbAudioSinkPrivate::Type* SbAudioSinkPrivate::GetPrimaryType() {
+SbAudioSinkImpl::Type* SbAudioSinkImpl::GetPrimaryType() {
   return primary_audio_sink_type;
 }
 // static
-void SbAudioSinkPrivate::EnableFallbackToStub() {
+void SbAudioSinkImpl::EnableFallbackToStub() {
   is_fallback_to_stub_enabled = true;
 }
 // static
-SbAudioSinkPrivate::Type* SbAudioSinkPrivate::GetFallbackType() {
+SbAudioSinkImpl::Type* SbAudioSinkImpl::GetFallbackType() {
   if (is_fallback_to_stub_enabled) {
     return fallback_audio_sink_type;
   }
@@ -82,17 +84,16 @@ SbAudioSinkPrivate::Type* SbAudioSinkPrivate::GetFallbackType() {
 }
 
 // static
-SbAudioSinkPrivate::Type* SbAudioSinkPrivate::GetPreferredType() {
-  SbAudioSinkPrivate::Type* audio_sink_type = NULL;
-  auto command_line =
-      starboard::shared::starboard::Application::Get()->GetCommandLine();
+SbAudioSinkImpl::Type* SbAudioSinkImpl::GetPreferredType() {
+  SbAudioSinkImpl::Type* audio_sink_type = NULL;
+  auto command_line = Application::Get()->GetCommandLine();
   if (!command_line->HasSwitch(kUseStubAudioSink)) {
-    audio_sink_type = SbAudioSinkPrivate::GetPrimaryType();
+    audio_sink_type = SbAudioSinkImpl::GetPrimaryType();
   }
   if (!audio_sink_type) {
     SB_LOG(WARNING) << "Primary audio sink type not selected or missing, "
                        "opting to use Fallback instead.";
-    audio_sink_type = SbAudioSinkPrivate::GetFallbackType();
+    audio_sink_type = SbAudioSinkImpl::GetFallbackType();
   }
   if (audio_sink_type == NULL) {
     SB_LOG(WARNING) << "Fallback audio sink type is not enabled.";
@@ -100,7 +101,7 @@ SbAudioSinkPrivate::Type* SbAudioSinkPrivate::GetPreferredType() {
   return audio_sink_type;
 }
 
-SbAudioSink SbAudioSinkPrivate::Create(
+SbAudioSink SbAudioSinkImpl::Create(
     int channels,
     int sampling_frequency_hz,
     SbMediaAudioSampleType audio_sample_type,
@@ -169,7 +170,7 @@ SbAudioSink SbAudioSinkPrivate::Create(
   }
 
   SB_LOG(WARNING) << "Try to create AudioSink using fallback type.";
-  if (auto fallback_type = SbAudioSinkPrivate::GetFallbackType()) {
+  if (auto fallback_type = SbAudioSinkImpl::GetFallbackType()) {
     auto audio_sink = fallback_type->Create(
         channels, sampling_frequency_hz, audio_sample_type,
         audio_frame_storage_type, frame_buffers, frame_buffers_size_in_frames,
@@ -186,7 +187,7 @@ SbAudioSink SbAudioSinkPrivate::Create(
 }
 
 // static
-SbAudioSink SbAudioSinkPrivate::Create(
+SbAudioSink SbAudioSinkImpl::Create(
     int channels,
     int sampling_frequency_hz,
     SbMediaAudioSampleType audio_sample_type,
@@ -201,8 +202,13 @@ SbAudioSink SbAudioSinkPrivate::Create(
                 audio_frame_storage_type, frame_buffers,
                 frame_buffers_size_in_frames, update_source_status_func,
                 sb_consume_frames_func
-                    ? std::bind(&::WrapConsumeFramesFunc,
-                                sb_consume_frames_func, _1, _2, _3)
+                    ? std::bind(&WrapConsumeFramesFunc, sb_consume_frames_func,
+                                _1, _2, _3)
                     : ConsumeFramesFunc(),
                 error_func, context);
 }
+
+}  // namespace audio_sink
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/shared/starboard/audio_sink/audio_sink_internal.h b/starboard/shared/starboard/audio_sink/audio_sink_internal.h
index fa0cc550d1f6..35c628c9f013 100644
--- a/starboard/shared/starboard/audio_sink/audio_sink_internal.h
+++ b/starboard/shared/starboard/audio_sink/audio_sink_internal.h
@@ -56,12 +56,19 @@ struct SbAudioSinkPrivate {
   };
 
   virtual ~SbAudioSinkPrivate() {}
-  virtual void SetPlaybackRate(double playback_rate) = 0;
 
+  virtual void SetPlaybackRate(double playback_rate) = 0;
   virtual void SetVolume(double volume) = 0;
-
   virtual bool IsType(Type* type) = 0;
+};
+
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace audio_sink {
 
+class SbAudioSinkImpl : public SbAudioSinkPrivate {
+ public:
   // The following two functions will be called during application startup and
   // termination.
   static void Initialize();
@@ -112,4 +119,9 @@ struct SbAudioSinkPrivate {
   static void PlatformTearDown();
 };
 
+}  // namespace audio_sink
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
+
 #endif  // STARBOARD_SHARED_STARBOARD_AUDIO_SINK_AUDIO_SINK_INTERNAL_H_
diff --git a/starboard/shared/starboard/audio_sink/audio_sink_is_valid.cc b/starboard/shared/starboard/audio_sink/audio_sink_is_valid.cc
index 05b2ceab0529..7e608a460260 100644
--- a/starboard/shared/starboard/audio_sink/audio_sink_is_valid.cc
+++ b/starboard/shared/starboard/audio_sink/audio_sink_is_valid.cc
@@ -17,11 +17,13 @@
 #include "starboard/shared/starboard/audio_sink/audio_sink_internal.h"
 
 bool SbAudioSinkIsValid(SbAudioSink audio_sink) {
-  SbAudioSinkPrivate::Type* type = SbAudioSinkPrivate::GetPrimaryType();
+  using ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl;
+
+  SbAudioSinkPrivate::Type* type = SbAudioSinkImpl::GetPrimaryType();
   if (type && type->IsValid(audio_sink)) {
     return true;
   }
-  type = SbAudioSinkPrivate::GetFallbackType();
+  type = SbAudioSinkImpl::GetFallbackType();
   if (type && type->IsValid(audio_sink)) {
     return true;
   }
diff --git a/starboard/shared/starboard/decode_target/decode_target_internal.h b/starboard/shared/starboard/decode_target/decode_target_internal.h
index f1db07cf338e..779ad897ddcb 100644
--- a/starboard/shared/starboard/decode_target/decode_target_internal.h
+++ b/starboard/shared/starboard/decode_target/decode_target_internal.h
@@ -20,7 +20,7 @@
 #include "starboard/common/ref_counted.h"
 
 struct SbDecodeTargetPrivate : starboard::RefCounted<SbDecodeTargetPrivate> {
-  SbDecodeTargetPrivate();
+  SbDecodeTargetPrivate() = default;
 
   SbDecodeTargetPrivate(const SbDecodeTargetPrivate&) = delete;
   SbDecodeTargetPrivate& operator=(const SbDecodeTargetPrivate&) = delete;
@@ -30,7 +30,7 @@ struct SbDecodeTargetPrivate : starboard::RefCounted<SbDecodeTargetPrivate> {
  protected:
   friend class starboard::RefCounted<SbDecodeTargetPrivate>;
 
-  virtual ~SbDecodeTargetPrivate();
+  virtual ~SbDecodeTargetPrivate() = default;
 };
 
 #endif  // STARBOARD_SHARED_STARBOARD_DECODE_TARGET_DECODE_TARGET_INTERNAL_H_
diff --git a/starboard/shared/starboard/media/media_is_audio_supported_aac_and_opus.cc b/starboard/shared/starboard/media/media_is_audio_supported_aac_and_opus.cc
index e4689ca5c69e..772a81acd382 100644
--- a/starboard/shared/starboard/media/media_is_audio_supported_aac_and_opus.cc
+++ b/starboard/shared/starboard/media/media_is_audio_supported_aac_and_opus.cc
@@ -18,11 +18,14 @@
 #include "starboard/configuration_constants.h"
 #include "starboard/media.h"
 
-using ::starboard::shared::starboard::media::MimeType;
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
 
-bool SbMediaIsAudioSupported(SbMediaAudioCodec audio_codec,
-                             const MimeType* mime_type,
-                             int64_t bitrate) {
+bool MediaIsAudioSupported(SbMediaAudioCodec audio_codec,
+                           const MimeType* mime_type,
+                           int64_t bitrate) {
   if (audio_codec == kSbMediaAudioCodecAac) {
     return bitrate <= kSbMediaMaxAudioBitrateInBitsPerSecond;
   }
@@ -33,3 +36,8 @@ bool SbMediaIsAudioSupported(SbMediaAudioCodec audio_codec,
 
   return false;
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/shared/starboard/media/media_is_audio_supported_aac_only.cc b/starboard/shared/starboard/media/media_is_audio_supported_aac_only.cc
index 83dbd141b4e8..d6c10617d436 100644
--- a/starboard/shared/starboard/media/media_is_audio_supported_aac_only.cc
+++ b/starboard/shared/starboard/media/media_is_audio_supported_aac_only.cc
@@ -18,11 +18,19 @@
 #include "starboard/configuration_constants.h"
 #include "starboard/media.h"
 
-using ::starboard::shared::starboard::media::MimeType;
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
 
-bool SbMediaIsAudioSupported(SbMediaAudioCodec audio_codec,
-                             const MimeType* mime_type,
-                             int64_t bitrate) {
+bool MediaIsAudioSupported(SbMediaAudioCodec audio_codec,
+                           const MimeType* mime_type,
+                           int64_t bitrate) {
   return audio_codec == kSbMediaAudioCodecAac &&
          bitrate <= kSbMediaMaxAudioBitrateInBitsPerSecond;
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/shared/starboard/media/media_support_internal.h b/starboard/shared/starboard/media/media_support_internal.h
index 31481482a8de..89d959302a17 100644
--- a/starboard/shared/starboard/media/media_support_internal.h
+++ b/starboard/shared/starboard/media/media_support_internal.h
@@ -20,9 +20,10 @@
 #include "starboard/shared/internal_only.h"
 #include "starboard/shared/starboard/media/mime_type.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
 
 // Indicates whether this platform supports decoding |video_codec| and
 // |audio_codec| along with decrypting using |key_system|. If |video_codec| is
@@ -35,9 +36,9 @@ extern "C" {
 // |audio_codec|: The |SbMediaAudioCodec| being checked for platform
 //                compatibility.
 // |key_system|: The key system being checked for platform compatibility.
-SB_EXPORT bool SbMediaIsSupported(SbMediaVideoCodec video_codec,
-                                  SbMediaAudioCodec audio_codec,
-                                  const char* key_system);
+SB_EXPORT bool MediaIsSupported(SbMediaVideoCodec video_codec,
+                                SbMediaAudioCodec audio_codec,
+                                const char* key_system);
 
 // Indicates whether a given combination of (|frame_width| x |frame_height|)
 // frames at |bitrate| and |fps| is supported on this platform with
@@ -73,20 +74,19 @@ SB_EXPORT bool SbMediaIsSupported(SbMediaVideoCodec video_codec,
 //        it indicates that the fps shouldn't be considered.
 // |decode_to_texture_required|: Whether or not the resulting video frames can
 //                               be decoded and used as textures by the GPU.
-bool SbMediaIsVideoSupported(
-    SbMediaVideoCodec video_codec,
-    const starboard::shared::starboard::media::MimeType* mime_type,
-    int profile,
-    int level,
-    int bit_depth,
-    SbMediaPrimaryId primary_id,
-    SbMediaTransferId transfer_id,
-    SbMediaMatrixId matrix_id,
-    int frame_width,
-    int frame_height,
-    int64_t bitrate,
-    int fps,
-    bool decode_to_texture_required);
+bool MediaIsVideoSupported(SbMediaVideoCodec video_codec,
+                           const MimeType* mime_type,
+                           int profile,
+                           int level,
+                           int bit_depth,
+                           SbMediaPrimaryId primary_id,
+                           SbMediaTransferId transfer_id,
+                           SbMediaMatrixId matrix_id,
+                           int frame_width,
+                           int frame_height,
+                           int64_t bitrate,
+                           int fps,
+                           bool decode_to_texture_required);
 
 // Indicates whether this platform supports |audio_codec| at |bitrate|.
 // If |audio_codec| is not supported under any condition, this function
@@ -96,13 +96,13 @@ bool SbMediaIsVideoSupported(
 // |mime_type|: The parsed mime type passed to the corresponding interface.
 //              Note that |mime_type| can be NULL.
 // |bitrate|: The media's bitrate.
-bool SbMediaIsAudioSupported(
-    SbMediaAudioCodec audio_codec,
-    const starboard::shared::starboard::media::MimeType* mime_type,
-    int64_t bitrate);
+bool MediaIsAudioSupported(SbMediaAudioCodec audio_codec,
+                           const MimeType* mime_type,
+                           int64_t bitrate);
 
-#ifdef __cplusplus
-}  // extern "C"
-#endif
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
 
 #endif  // STARBOARD_SHARED_STARBOARD_MEDIA_MEDIA_SUPPORT_INTERNAL_H_
diff --git a/starboard/shared/starboard/media/mime_util.cc b/starboard/shared/starboard/media/mime_util.cc
index e0fc0280558d..a3c0b2ce4815 100644
--- a/starboard/shared/starboard/media/mime_util.cc
+++ b/starboard/shared/starboard/media/mime_util.cc
@@ -59,7 +59,7 @@ bool IsSupportedKeySystem(SbMediaAudioCodec codec, const char* key_system) {
   // |key_system|, so here it should always be non empty.
   SB_DCHECK(strlen(key_system) > 0);
 
-  return SbMediaIsSupported(kSbMediaVideoCodecNone, codec, key_system);
+  return MediaIsSupported(kSbMediaVideoCodecNone, codec, key_system);
 }
 
 bool IsSupportedKeySystem(SbMediaVideoCodec codec, const char* key_system) {
@@ -68,7 +68,7 @@ bool IsSupportedKeySystem(SbMediaVideoCodec codec, const char* key_system) {
   // |key_system|, so here it should always be non empty.
   SB_DCHECK(strlen(key_system) > 0);
 
-  return SbMediaIsSupported(codec, kSbMediaAudioCodecNone, key_system);
+  return MediaIsSupported(codec, kSbMediaAudioCodecNone, key_system);
 }
 
 bool IsSupportedAudioCodec(const ParsedMimeInfo& mime_info) {
@@ -123,8 +123,8 @@ bool IsSupportedAudioCodec(const ParsedMimeInfo& mime_info) {
     return false;
   }
 
-  return SbMediaIsAudioSupported(audio_info.codec, &mime_type,
-                                 audio_info.bitrate);
+  return MediaIsAudioSupported(audio_info.codec, &mime_type,
+                               audio_info.bitrate);
 }
 
 bool IsSupportedVideoCodec(const ParsedMimeInfo& mime_info) {
@@ -175,7 +175,7 @@ bool IsSupportedVideoCodec(const ParsedMimeInfo& mime_info) {
     }
   }
 
-  return SbMediaIsVideoSupported(
+  return MediaIsVideoSupported(
       video_info.codec, &mime_type, video_info.profile, video_info.level,
       video_info.bit_depth, video_info.primary_id, video_info.transfer_id,
       video_info.matrix_id, video_info.frame_width, video_info.frame_height,
diff --git a/starboard/shared/starboard/media/mime_util_test.cc b/starboard/shared/starboard/media/mime_util_test.cc
index 8cfcb6495b14..c21469cef20c 100644
--- a/starboard/shared/starboard/media/mime_util_test.cc
+++ b/starboard/shared/starboard/media/mime_util_test.cc
@@ -35,8 +35,7 @@ TEST(MimeUtilTest, ChecksSupportedMp3Containers) {
   const MimeType valid_mp3_mime_1(valid_mp3_mime_str_1);
   EXPECT_EQ(
       CanPlayMimeAndKeySystem(valid_mp3_mime_str_1.c_str(), kEmptyKeySystem),
-      SbMediaIsAudioSupported(kSbMediaAudioCodecMp3, &valid_mp3_mime_1,
-                              kBitrate)
+      MediaIsAudioSupported(kSbMediaAudioCodecMp3, &valid_mp3_mime_1, kBitrate)
           ? kSbMediaSupportTypeProbably
           : kSbMediaSupportTypeNotSupported);
 
@@ -45,8 +44,7 @@ TEST(MimeUtilTest, ChecksSupportedMp3Containers) {
   const MimeType valid_mp3_mime_2(valid_mp3_mime_str_2);
   EXPECT_EQ(
       CanPlayMimeAndKeySystem(valid_mp3_mime_str_2.c_str(), kEmptyKeySystem),
-      SbMediaIsAudioSupported(kSbMediaAudioCodecMp3, &valid_mp3_mime_2,
-                              kBitrate)
+      MediaIsAudioSupported(kSbMediaAudioCodecMp3, &valid_mp3_mime_2, kBitrate)
           ? kSbMediaSupportTypeProbably
           : kSbMediaSupportTypeNotSupported);
 }
@@ -67,8 +65,7 @@ TEST(MimeUtilTest, ChecksSupportedFlacContainers) {
   const MimeType valid_flac_mime_1(valid_flac_mime_str_1);
   EXPECT_EQ(
       CanPlayMimeAndKeySystem(valid_flac_mime_str_1.c_str(), kEmptyKeySystem),
-      SbMediaIsAudioSupported(kSbMediaAudioCodecMp3, &valid_flac_mime_1,
-                              kBitrate)
+      MediaIsAudioSupported(kSbMediaAudioCodecMp3, &valid_flac_mime_1, kBitrate)
           ? kSbMediaSupportTypeProbably
           : kSbMediaSupportTypeNotSupported);
 
@@ -77,8 +74,7 @@ TEST(MimeUtilTest, ChecksSupportedFlacContainers) {
   const MimeType valid_flac_mime_2(valid_flac_mime_str_2);
   EXPECT_EQ(
       CanPlayMimeAndKeySystem(valid_flac_mime_str_2.c_str(), kEmptyKeySystem),
-      SbMediaIsAudioSupported(kSbMediaAudioCodecMp3, &valid_flac_mime_2,
-                              kBitrate)
+      MediaIsAudioSupported(kSbMediaAudioCodecMp3, &valid_flac_mime_2, kBitrate)
           ? kSbMediaSupportTypeProbably
           : kSbMediaSupportTypeNotSupported);
 }
@@ -99,7 +95,7 @@ TEST(MimeUtilTest, ChecksSupportedPcmContainers) {
   const MimeType valid_pcm_mime(valid_pcm_mime_str);
   EXPECT_EQ(
       CanPlayMimeAndKeySystem(valid_pcm_mime_str.c_str(), kEmptyKeySystem),
-      SbMediaIsAudioSupported(kSbMediaAudioCodecPcm, &valid_pcm_mime, kBitrate)
+      MediaIsAudioSupported(kSbMediaAudioCodecPcm, &valid_pcm_mime, kBitrate)
           ? kSbMediaSupportTypeProbably
           : kSbMediaSupportTypeNotSupported);
 }
diff --git a/starboard/shared/starboard/player/filter/audio_renderer_sink_impl.cc b/starboard/shared/starboard/player/filter/audio_renderer_sink_impl.cc
index 1f7ad987833e..d0569f3c78d8 100644
--- a/starboard/shared/starboard/player/filter/audio_renderer_sink_impl.cc
+++ b/starboard/shared/starboard/player/filter/audio_renderer_sink_impl.cc
@@ -39,7 +39,7 @@ AudioRendererSinkImpl::AudioRendererSinkImpl()
              SbAudioSinkPrivate::ConsumeFramesFunc consume_frames_func,
              SbAudioSinkPrivate::ErrorFunc error_func,
              void* context) {
-            return SbAudioSinkPrivate::Create(
+            return audio_sink::SbAudioSinkImpl::Create(
                 channels, sampling_frequency_hz, audio_sample_type,
                 audio_frame_storage_type, frame_buffers,
                 frame_buffers_size_in_frames, update_source_status_func,
diff --git a/starboard/shared/starboard/player/filter/testing/test_util.cc b/starboard/shared/starboard/player/filter/testing/test_util.cc
index fd99aee105d8..05585ac0614b 100644
--- a/starboard/shared/starboard/player/filter/testing/test_util.cc
+++ b/starboard/shared/starboard/player/filter/testing/test_util.cc
@@ -143,8 +143,8 @@ std::vector<const char*> GetSupportedAudioTestFiles(
     const std::string audio_mime = GetContentTypeFromAudioCodec(
         audio_file_info.audio_codec, extra_mime_attributes);
     const MimeType audio_mime_type(audio_mime.c_str());
-    if (!SbMediaIsAudioSupported(audio_file_info.audio_codec, &audio_mime_type,
-                                 audio_file_info.bitrate)) {
+    if (!MediaIsAudioSupported(audio_file_info.audio_codec, &audio_mime_type,
+                               audio_file_info.bitrate)) {
       continue;
     }
 
@@ -186,7 +186,7 @@ std::vector<VideoTestParam> GetSupportedVideoTests() {
       const auto& video_stream_info = dmp_reader.video_stream_info();
       const std::string video_mime = dmp_reader.video_mime_type();
       const MimeType video_mime_type(video_mime.c_str());
-      // SbMediaIsVideoSupported may return false for gpu based decoder that in
+      // MediaIsVideoSupported may return false for gpu based decoder that in
       // fact supports av1 or/and vp9 because the system can make async
       // initialization at startup.
       // To minimize probability of false negative we check result few times
@@ -196,7 +196,7 @@ std::vector<VideoTestParam> GetSupportedVideoTests() {
       bool need_to_check_with_wait = video_codec == kSbMediaVideoCodecAv1 ||
                                      video_codec == kSbMediaVideoCodecVp9;
       do {
-        if (SbMediaIsVideoSupported(
+        if (MediaIsVideoSupported(
                 video_codec, video_mime.size() > 0 ? &video_mime_type : nullptr,
                 -1, -1, 8, kSbMediaPrimaryIdUnspecified,
                 kSbMediaTransferIdUnspecified, kSbMediaMatrixIdUnspecified,
diff --git a/starboard/shared/starboard/player/player_create.cc b/starboard/shared/starboard/player/player_create.cc
index 5e86db11b056..427fa3ef0bc8 100644
--- a/starboard/shared/starboard/player/player_create.cc
+++ b/starboard/shared/starboard/player/player_create.cc
@@ -132,7 +132,7 @@ SbPlayer SbPlayerCreate(SbWindow window,
   const int64_t kDefaultBitRate = 0;
   if (audio_codec != kSbMediaAudioCodecNone) {
     const MimeType audio_mime_type(audio_mime);
-    if (!SbMediaIsAudioSupported(
+    if (!MediaIsAudioSupported(
             audio_codec, strlen(audio_mime) > 0 ? &audio_mime_type : nullptr,
             kDefaultBitRate)) {
       SB_LOG(ERROR) << "Unsupported audio codec "
@@ -154,7 +154,7 @@ SbPlayer SbPlayerCreate(SbWindow window,
   const int kDefaultFrameRate = 0;
   if (video_codec != kSbMediaVideoCodecNone) {
     const MimeType video_mime_type(video_mime);
-    if (!SbMediaIsVideoSupported(
+    if (!MediaIsVideoSupported(
             video_codec, strlen(video_mime) > 0 ? &video_mime_type : nullptr,
             kDefaultProfile, kDefaultLevel, kDefaultColorDepth,
             kSbMediaPrimaryIdUnspecified, kSbMediaTransferIdUnspecified,
diff --git a/starboard/shared/stub/media_is_audio_supported.cc b/starboard/shared/stub/media_is_audio_supported.cc
index 853eca07306b..a8625a993aaf 100644
--- a/starboard/shared/stub/media_is_audio_supported.cc
+++ b/starboard/shared/stub/media_is_audio_supported.cc
@@ -16,10 +16,18 @@
 
 #include "starboard/media.h"
 
-using ::starboard::shared::starboard::media::MimeType;
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
 
-bool SbMediaIsAudioSupported(SbMediaAudioCodec audio_codec,
-                             const MimeType* mime_type,
-                             int64_t bitrate) {
+bool MediaIsAudioSupported(SbMediaAudioCodec audio_codec,
+                           const MimeType* mime_type,
+                           int64_t bitrate) {
   return false;
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/shared/stub/media_is_supported.cc b/starboard/shared/stub/media_is_supported.cc
index fd53e2e10cfa..6e07c4992dd0 100644
--- a/starboard/shared/stub/media_is_supported.cc
+++ b/starboard/shared/stub/media_is_supported.cc
@@ -16,8 +16,18 @@
 
 #include "starboard/media.h"
 
-bool SbMediaIsSupported(SbMediaVideoCodec video_codec,
-                        SbMediaAudioCodec audio_codec,
-                        const char* key_system) {
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
+
+bool MediaIsSupported(SbMediaVideoCodec video_codec,
+                      SbMediaAudioCodec audio_codec,
+                      const char* key_system) {
   return false;
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/shared/stub/media_is_video_supported.cc b/starboard/shared/stub/media_is_video_supported.cc
index 1049791d09ee..6b6d4fbdc648 100644
--- a/starboard/shared/stub/media_is_video_supported.cc
+++ b/starboard/shared/stub/media_is_video_supported.cc
@@ -16,20 +16,28 @@
 
 #include "starboard/media.h"
 
-using ::starboard::shared::starboard::media::MimeType;
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
 
-bool SbMediaIsVideoSupported(SbMediaVideoCodec video_codec,
-                             const MimeType* mime_type,
-                             int profile,
-                             int level,
-                             int bit_depth,
-                             SbMediaPrimaryId primary_id,
-                             SbMediaTransferId transfer_id,
-                             SbMediaMatrixId matrix_id,
-                             int frame_width,
-                             int frame_height,
-                             int64_t bitrate,
-                             int fps,
-                             bool decode_to_texture_required) {
+bool MediaIsVideoSupported(SbMediaVideoCodec video_codec,
+                           const MimeType* mime_type,
+                           int profile,
+                           int level,
+                           int bit_depth,
+                           SbMediaPrimaryId primary_id,
+                           SbMediaTransferId transfer_id,
+                           SbMediaMatrixId matrix_id,
+                           int frame_width,
+                           int frame_height,
+                           int64_t bitrate,
+                           int fps,
+                           bool decode_to_texture_required) {
   return false;
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/shared/widevine/media_is_supported.cc b/starboard/shared/widevine/media_is_supported.cc
index 413fd22367a1..fc0bcb6bd9be 100644
--- a/starboard/shared/widevine/media_is_supported.cc
+++ b/starboard/shared/widevine/media_is_supported.cc
@@ -17,10 +17,20 @@
 #include "starboard/media.h"
 #include "starboard/shared/widevine/drm_system_widevine.h"
 
-bool SbMediaIsSupported(SbMediaVideoCodec video_codec,
-                        SbMediaAudioCodec audio_codec,
-                        const char* key_system) {
-  using starboard::shared::widevine::DrmSystemWidevine;
+namespace starboard {
+namespace shared {
+namespace starboard {
+namespace media {
+
+bool MediaIsSupported(SbMediaVideoCodec video_codec,
+                      SbMediaAudioCodec audio_codec,
+                      const char* key_system) {
+  using ::starboard::shared::widevine::DrmSystemWidevine;
 
   return DrmSystemWidevine::IsKeySystemSupported(key_system);
 }
+
+}  // namespace media
+}  // namespace starboard
+}  // namespace shared
+}  // namespace starboard
diff --git a/starboard/shared/x11/application_x11.cc b/starboard/shared/x11/application_x11.cc
index c6a838efa5d1..bac7cd074507 100644
--- a/starboard/shared/x11/application_x11.cc
+++ b/starboard/shared/x11/application_x11.cc
@@ -701,12 +701,12 @@ ApplicationX11::ApplicationX11(SbEventHandleCallback sb_event_handle_callback)
       composite_event_id_(kSbEventIdInvalid),
       display_(NULL),
       paste_buffer_key_release_pending_(false) {
-  SbAudioSinkPrivate::Initialize();
+  ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl::Initialize();
   NetworkNotifier::GetOrCreateInstance();
 }
 
 ApplicationX11::~ApplicationX11() {
-  SbAudioSinkPrivate::TearDown();
+  ::starboard::shared::starboard::audio_sink::SbAudioSinkImpl::TearDown();
 }
 
 SbWindow ApplicationX11::CreateWindow(const SbWindowOptions* options) {
diff --git a/third_party/android_deps/.gitignore b/third_party/android_deps/.gitignore
index 8066eb49d992..2c0c14b59480 100644
--- a/third_party/android_deps/.gitignore
+++ b/third_party/android_deps/.gitignore
@@ -6,6 +6,7 @@ buildSrc/.gradle/
 buildSrc/build/
 
 # JAR and AAR files will be fetched via CIPD.
+cipd/
 libs/*/*.jar
 libs/*/*.aar
 
diff --git a/third_party/blink/public/mojom/BUILD.gn b/third_party/blink/public/mojom/BUILD.gn
index b1145a98a6d1..a4f61e8fca99 100644
--- a/third_party/blink/public/mojom/BUILD.gn
+++ b/third_party/blink/public/mojom/BUILD.gn
@@ -241,6 +241,10 @@ mojom("mojom_platform") {
     "worker/worker_options.mojom",
   ]
 
+  if (is_cobalt) {
+    sources += [ "cobalt/crash_annotator/crash_annotator.mojom" ]
+  }
+
   if (is_android) {
     sources += [ "input/synchronous_compositor.mojom" ]
   }
diff --git a/third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom b/third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom
new file mode 100644
index 000000000000..84deafd8df26
--- /dev/null
+++ b/third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom
@@ -0,0 +1,22 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+module blink.mojom;
+
+// The browser process must provide an implementation of this interface so that
+// the renderer process can implement the CrashAnnotator Blink API.
+interface CrashAnnotator {
+  // Recieves an annotation to set and responds with the result.
+  SetString(string key, string value) => (bool result);
+};
diff --git a/third_party/blink/public/platform/web_source_buffer.h b/third_party/blink/public/platform/web_source_buffer.h
index 7ac41eedb64f..fc3defa085be 100644
--- a/third_party/blink/public/platform/web_source_buffer.h
+++ b/third_party/blink/public/platform/web_source_buffer.h
@@ -37,6 +37,10 @@
 
 namespace blink {
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+class ExceptionState;
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
 class WebSourceBufferClient;
 
 // Interface for actuating the media engine implementation of Media Source
@@ -140,6 +144,11 @@ class WebSourceBuffer {
   // After this method is called, this WebSourceBuffer should never use the
   // client pointer passed to SetClient().
   virtual void RemovedFromMediaSource() = 0;
+
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+  // Return the highest presentation timestamp written to the Renderer.
+  virtual double GetWriteHead(ExceptionState& exception_state) const = 0;
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
 };
 
 }  // namespace blink
diff --git a/third_party/blink/renderer/bindings/generated_in_modules.gni b/third_party/blink/renderer/bindings/generated_in_modules.gni
index 0b3ea3360c6c..118f11e214c6 100644
--- a/third_party/blink/renderer/bindings/generated_in_modules.gni
+++ b/third_party/blink/renderer/bindings/generated_in_modules.gni
@@ -2791,6 +2791,13 @@ generated_interface_sources_in_modules = [
   "$root_gen_dir/third_party/blink/renderer/bindings/modules/v8/v8_xr_webgl_sub_image.h",
 ]
 
+if (is_cobalt) {
+  generated_interface_sources_in_modules += [
+    "$root_gen_dir/third_party/blink/renderer/bindings/modules/v8/v8_crash_annotator.cc",
+    "$root_gen_dir/third_party/blink/renderer/bindings/modules/v8/v8_crash_annotator.h",
+  ]
+}
+
 generated_namespace_sources_in_modules = [
   "$root_gen_dir/third_party/blink/renderer/bindings/modules/v8/v8_css.cc",
   "$root_gen_dir/third_party/blink/renderer/bindings/modules/v8/v8_css.h",
diff --git a/third_party/blink/renderer/bindings/idl_in_modules.gni b/third_party/blink/renderer/bindings/idl_in_modules.gni
index 7f915ac9c55d..3445984b8088 100644
--- a/third_party/blink/renderer/bindings/idl_in_modules.gni
+++ b/third_party/blink/renderer/bindings/idl_in_modules.gni
@@ -4,6 +4,10 @@
 
 import("//third_party/blink/renderer/config.gni")
 
+if (is_cobalt) {
+  import("//starboard/build/buildflags.gni")
+}
+
 # Statically-defined (not build-time-generated) IDL files in 'modules' component
 # for production.
 static_idl_files_in_modules = get_path_info(
@@ -1202,6 +1206,15 @@ static_idl_files_in_modules = get_path_info(
         ],
         "abspath")
 
+if (is_cobalt) {
+  static_idl_files_in_modules += get_path_info(
+          [
+            "//third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.idl",
+            "//third_party/blink/renderer/modules/cobalt/crash_annotator/navigator_crash_annotator.idl",
+          ],
+          "abspath")
+}
+
 # Direct Sockets
 # This uses target_os rather than current_os (which is what is_android is set
 # from) for the case of generating the v8 context snapshot for android. When
@@ -1279,6 +1292,15 @@ if (target_os != "android") {
           "abspath")
 }
 
+# SourceBufferWriteHead
+# An extension to the SourceBuffer interface that allows web apps to check the
+# highest presentation timestamp written to the Renderer.
+if (is_cobalt && use_starboard_media) {
+  static_idl_files_in_modules += get_path_info(
+          [ "//third_party/blink/renderer/modules/mediasource/source_buffer_write_head.idl" ],
+          "abspath")
+}
+
 # Statically-defined (not runtime-generated) IDL files in 'modules' component.
 # These IDL definitions are used only for testing.
 static_idl_files_in_modules_for_testing = get_path_info(
diff --git a/third_party/blink/renderer/core/html/media/html_media_element.cc b/third_party/blink/renderer/core/html/media/html_media_element.cc
index 0ecba68e421f..e565c5c81d77 100644
--- a/third_party/blink/renderer/core/html/media/html_media_element.cc
+++ b/third_party/blink/renderer/core/html/media/html_media_element.cc
@@ -124,6 +124,7 @@
 // For BUILDFLAG(USE_STARBOARD_MEDIA)
 #include "build/build_config.h"
 #if BUILDFLAG(USE_STARBOARD_MEDIA)
+#include "base/strings/string_util.h"
 #include "starboard/media.h"
 #endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
 
@@ -408,7 +409,8 @@ std::ostream& operator<<(std::ostream& stream,
 #if BUILDFLAG(USE_STARBOARD_MEDIA)
 // Checks for progressive formats served by the YouTube H5 player.
 // These formats have a mime type of "video/mp4", and lists both audio and
-// video codecs under the "codecs" parameter.
+// video codecs under the "codecs" parameter. This is not a comprehensive
+// check and may not detect all progressive formats.
 bool IsProgressiveFormat(const ContentType& content_type) {
   const String type = content_type.GetType();
   const String codecs = content_type.Parameter("codecs");
@@ -418,7 +420,7 @@ bool IsProgressiveFormat(const ContentType& content_type) {
   }
 
   Vector<String> split_codecs;
-  const String separator(", ");
+  const String separator(",");
   codecs.Split(separator, split_codecs);
   return type.Utf8() == "video/mp4" && split_codecs.size() == 2;
 }
diff --git a/third_party/blink/renderer/core/html/media/html_media_element_test.cc b/third_party/blink/renderer/core/html/media/html_media_element_test.cc
index 81841cfae1d3..c3439a87a486 100644
--- a/third_party/blink/renderer/core/html/media/html_media_element_test.cc
+++ b/third_party/blink/renderer/core/html/media/html_media_element_test.cc
@@ -1578,6 +1578,8 @@ TEST_P(HTMLMediaElementTest, CanFreezeWithMediaPlayerAttached) {
 TEST(HTMLMediaElementTest, CanHandleCobaltProgressiveSupportQueries) {
   const ContentType progressive_type(
       "video/mp4; codecs=\"avc1.42001E, mp4a.40.2\"");
+  const ContentType progressive_type_missing_whitespace(
+      "video/mp4; codecs=\"avc1.42001E,mp4a.40.2\"");
   const ContentType adaptive_video_type(
       "video/mp4; codecs=\"avc1.4d4015\"; framerate=30");
   const ContentType adaptive_audio_type(
@@ -1590,6 +1592,11 @@ TEST(HTMLMediaElementTest, CanHandleCobaltProgressiveSupportQueries) {
     // disabled.
     EXPECT_EQ(HTMLMediaElement::GetSupportsType(progressive_type),
               MIMETypeRegistry::kNotSupported);
+    // Reject progressive content types when the "codecs" parameter lacks
+    // whitespace.
+    EXPECT_EQ(
+        HTMLMediaElement::GetSupportsType(progressive_type_missing_whitespace),
+        MIMETypeRegistry::kNotSupported);
     // Continue to support adaptive content types.
     EXPECT_NE(HTMLMediaElement::GetSupportsType(adaptive_video_type),
               MIMETypeRegistry::kNotSupported);
@@ -1603,6 +1610,11 @@ TEST(HTMLMediaElementTest, CanHandleCobaltProgressiveSupportQueries) {
     // enabled.
     EXPECT_NE(HTMLMediaElement::GetSupportsType(progressive_type),
               MIMETypeRegistry::kNotSupported);
+    // Continue to accept progressive content types when the "codecs" parameter
+    // lacks whitespace.
+    EXPECT_NE(
+        HTMLMediaElement::GetSupportsType(progressive_type_missing_whitespace),
+        MIMETypeRegistry::kNotSupported);
     // Continue to support adaptive content types.
     EXPECT_NE(HTMLMediaElement::GetSupportsType(adaptive_video_type),
               MIMETypeRegistry::kNotSupported);
diff --git a/third_party/blink/renderer/modules/BUILD.gn b/third_party/blink/renderer/modules/BUILD.gn
index 855d33552a2d..19a3b5f5ab47 100644
--- a/third_party/blink/renderer/modules/BUILD.gn
+++ b/third_party/blink/renderer/modules/BUILD.gn
@@ -167,6 +167,10 @@ component("modules") {
     "//third_party/blink/renderer/modules/xr",
   ]
 
+  if (is_cobalt) {
+    sub_modules += [ "//third_party/blink/renderer/modules/cobalt/crash_annotator" ]
+  }
+
   # This uses target_os rather than current_os (which is what is_android is set
   # from) for the case of generating the v8 context snapshot for android. When
   # generating the snapshot for android, blink is compiled with
diff --git a/third_party/blink/renderer/modules/cobalt/crash_annotator/BUILD.gn b/third_party/blink/renderer/modules/cobalt/crash_annotator/BUILD.gn
new file mode 100644
index 000000000000..cb5b0e61e73f
--- /dev/null
+++ b/third_party/blink/renderer/modules/cobalt/crash_annotator/BUILD.gn
@@ -0,0 +1,22 @@
+# Copyright 2024 The Cobalt Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import("//third_party/blink/renderer/modules/modules.gni")
+
+blink_modules_sources("crash_annotator") {
+  sources = [
+    "crash_annotator.cc",
+    "crash_annotator.h",
+  ]
+}
diff --git a/third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.cc b/third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.cc
new file mode 100644
index 000000000000..4485eadbe71a
--- /dev/null
+++ b/third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.cc
@@ -0,0 +1,92 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.h"
+
+#include "mojo/public/cpp/bindings/pending_receiver.h"
+#include "mojo/public/cpp/bindings/remote.h"
+#include "third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom-blink.h"
+#include "third_party/blink/renderer/bindings/core/v8/script_promise.h"
+#include "third_party/blink/renderer/bindings/core/v8/script_promise_resolver.h"
+#include "third_party/blink/renderer/core/execution_context/execution_context.h"
+#include "third_party/blink/renderer/core/execution_context/navigator_base.h"
+#include "third_party/blink/renderer/platform/bindings/exception_state.h"
+#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"
+
+namespace blink {
+
+// static
+const char CrashAnnotator::kSupplementName[] = "CrashAnnotator";
+
+// static
+CrashAnnotator* CrashAnnotator::crashAnnotator(NavigatorBase& navigator) {
+  CrashAnnotator* crash_annotator =
+      Supplement<NavigatorBase>::From<CrashAnnotator>(navigator);
+  if (!crash_annotator && navigator.GetExecutionContext()) {
+    crash_annotator = MakeGarbageCollected<CrashAnnotator>(navigator);
+    ProvideTo(navigator, crash_annotator);
+  }
+  return crash_annotator;
+}
+
+CrashAnnotator::CrashAnnotator(NavigatorBase& navigator)
+    : Supplement<NavigatorBase>(navigator),
+      ExecutionContextLifecycleObserver(navigator.GetExecutionContext()),
+      crash_annotator_(navigator.GetExecutionContext()) {}
+
+void CrashAnnotator::ContextDestroyed() {}
+
+ScriptPromise CrashAnnotator::setString(ScriptState* script_state,
+                                        const String& key,
+                                        const String& value,
+                                        ExceptionState& exception_state) {
+  auto* resolver = MakeGarbageCollected<ScriptPromiseResolver>(
+      script_state, exception_state.GetContext());
+
+  EnsureReceiverIsBound();
+
+  crash_annotator_->SetString(key,
+                              value,
+                              WTF::BindOnce(
+                                  &CrashAnnotator::OnSetString,
+                                  WrapPersistent(this), WrapPersistent(resolver)));
+
+  return resolver->Promise();
+}
+
+void CrashAnnotator::OnSetString(ScriptPromiseResolver* resolver, bool result) {
+  resolver->Resolve(result);
+}
+
+void CrashAnnotator::EnsureReceiverIsBound() {
+  DCHECK(GetExecutionContext());
+
+  if (crash_annotator_.is_bound()) {
+    return;
+  }
+
+  auto task_runner =
+      GetExecutionContext()->GetTaskRunner(TaskType::kMiscPlatformAPI);
+  GetExecutionContext()->GetBrowserInterfaceBroker().GetInterface(
+      crash_annotator_.BindNewPipeAndPassReceiver(task_runner));
+}
+
+void CrashAnnotator::Trace(Visitor* visitor) const {
+  visitor->Trace(crash_annotator_);
+  Supplement<NavigatorBase>::Trace(visitor);
+  ExecutionContextLifecycleObserver::Trace(visitor);
+  ScriptWrappable::Trace(visitor);
+}
+
+}  // namespace blink
diff --git a/third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.h b/third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.h
new file mode 100644
index 000000000000..1ea37ac1e1a0
--- /dev/null
+++ b/third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.h
@@ -0,0 +1,66 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef THIRD_PARTY_BLINK_RENDERER_MODULES_COBALT_CRASH_ANNOTATOR_H_
+#define THIRD_PARTY_BLINK_RENDERER_MODULES_COBALT_CRASH_ANNOTATOR_H_
+
+#include "third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom-blink.h"
+#include "third_party/blink/renderer/bindings/core/v8/script_promise.h"
+#include "third_party/blink/renderer/core/execution_context/execution_context_lifecycle_observer.h"
+#include "third_party/blink/renderer/modules/modules_export.h"
+#include "third_party/blink/renderer/platform/bindings/script_wrappable.h"
+#include "third_party/blink/renderer/platform/mojo/heap_mojo_receiver.h"
+#include "third_party/blink/renderer/platform/mojo/heap_mojo_remote.h"
+#include "third_party/blink/renderer/platform/mojo/heap_mojo_wrapper_mode.h"
+
+namespace blink {
+
+class ExecutionContext;
+class NavigatorBase;
+class ScriptPromiseResolver;
+class ScriptState;
+
+class MODULES_EXPORT CrashAnnotator final
+    : public ScriptWrappable,
+      public Supplement<NavigatorBase>,
+      public ExecutionContextLifecycleObserver {
+  DEFINE_WRAPPERTYPEINFO();
+
+ public:
+  static const char kSupplementName[];
+
+  // For navigator.crashAnnotator
+  static CrashAnnotator* crashAnnotator(NavigatorBase&);
+
+  explicit CrashAnnotator(NavigatorBase&);
+
+  void ContextDestroyed() override;
+
+  ScriptPromise setString(ScriptState*,
+                          const String& key,
+                          const String& value,
+                          ExceptionState&);
+
+  void Trace(Visitor*) const override;
+
+ private:
+  void OnSetString(ScriptPromiseResolver*, bool);
+  void EnsureReceiverIsBound();
+
+  HeapMojoRemote<mojom::blink::CrashAnnotator> crash_annotator_;
+};
+
+}  // namespace blink
+
+#endif  // THIRD_PARTY_BLINK_RENDERER_MODULES_COBALT_CRASH_ANNOTATOR_H_
diff --git a/third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.idl b/third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.idl
new file mode 100644
index 000000000000..9f8596e5456d
--- /dev/null
+++ b/third_party/blink/renderer/modules/cobalt/crash_annotator/crash_annotator.idl
@@ -0,0 +1,24 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Allows (key, value) pairs to be added to uploaded crash reports as context.
+[
+    Exposed=Window,
+    SecureContext
+]
+interface CrashAnnotator {
+    // Returns a promise of true on success and false on failure.
+    [CallWith=ScriptState, RaisesException]
+    Promise<boolean> setString(DOMString key, DOMString value);
+};
diff --git a/starboard/shared/starboard/decode_target/decode_target_internal.cc b/third_party/blink/renderer/modules/cobalt/crash_annotator/navigator_crash_annotator.idl
similarity index 76%
rename from starboard/shared/starboard/decode_target/decode_target_internal.cc
rename to third_party/blink/renderer/modules/cobalt/crash_annotator/navigator_crash_annotator.idl
index 29c40807efed..737ff89f910a 100644
--- a/starboard/shared/starboard/decode_target/decode_target_internal.cc
+++ b/third_party/blink/renderer/modules/cobalt/crash_annotator/navigator_crash_annotator.idl
@@ -12,8 +12,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "starboard/shared/starboard/decode_target/decode_target_internal.h"
-
-SbDecodeTargetPrivate::SbDecodeTargetPrivate() = default;
-
-SbDecodeTargetPrivate::~SbDecodeTargetPrivate() = default;
+// Extends the navigator interface.
+[
+  ImplementedAs=CrashAnnotator,
+  SecureContext
+] partial interface Navigator {
+  [SameObject] readonly attribute CrashAnnotator crashAnnotator;
+};
diff --git a/third_party/blink/renderer/modules/mediasource/BUILD.gn b/third_party/blink/renderer/modules/mediasource/BUILD.gn
index a14bb0a20c07..0d8b68a606f5 100644
--- a/third_party/blink/renderer/modules/mediasource/BUILD.gn
+++ b/third_party/blink/renderer/modules/mediasource/BUILD.gn
@@ -56,8 +56,10 @@ blink_modules_sources("mediasource") {
     "//third_party/blink/renderer/modules/webcodecs:webcodecs",
   ]
   if (is_cobalt && use_starboard_media) {
-    deps += [
-      "//starboard($starboard_toolchain)",
+    sources += [
+      "source_buffer_write_head.cc",
+      "source_buffer_write_head.h",
     ]
+    deps += [ "//starboard($starboard_toolchain)" ]
   }
 }
diff --git a/third_party/blink/renderer/modules/mediasource/source_buffer.cc b/third_party/blink/renderer/modules/mediasource/source_buffer.cc
index 42a23253da5b..5cdd7a0ac68c 100644
--- a/third_party/blink/renderer/modules/mediasource/source_buffer.cc
+++ b/third_party/blink/renderer/modules/mediasource/source_buffer.cc
@@ -475,6 +475,20 @@ VideoTrackList& SourceBuffer::videoTracks() {
   return *video_tracks_;
 }
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+double SourceBuffer::GetWriteHead(ExceptionState& exception_state) const {
+  if (source_ == NULL) {
+    MediaSource::LogAndThrowDOMException(
+        exception_state, DOMExceptionCode::kInvalidStateError,
+        "Cannot obtain SourceBuffer write head with an invalid MediaSource");
+    return 0.0;
+  }
+
+  DCHECK(web_source_buffer_);
+  return web_source_buffer_->GetWriteHead(exception_state);
+}
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
 double SourceBuffer::appendWindowStart() const {
   return append_window_start_;
 }
diff --git a/third_party/blink/renderer/modules/mediasource/source_buffer.h b/third_party/blink/renderer/modules/mediasource/source_buffer.h
index 0178bf1a8e66..0ac28dca70f0 100644
--- a/third_party/blink/renderer/modules/mediasource/source_buffer.h
+++ b/third_party/blink/renderer/modules/mediasource/source_buffer.h
@@ -113,6 +113,12 @@ class SourceBuffer final : public EventTargetWithInlineData,
   AudioTrackList& audioTracks();
   VideoTrackList& videoTracks();
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+  // Cobalt-specific method that returns the highest presentation
+  // timestamp written to the Renderer.
+  double GetWriteHead(ExceptionState& exception_state) const;
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
   // "_Locked" requires these be called while in the scope of callback of
   // |source_|'s attachment's RunExclusively(). Other methods without "_Locked"
   // may also require the same, since they can be called from within these
diff --git a/third_party/blink/renderer/modules/mediasource/source_buffer_write_head.cc b/third_party/blink/renderer/modules/mediasource/source_buffer_write_head.cc
new file mode 100644
index 000000000000..578ba3a42e0c
--- /dev/null
+++ b/third_party/blink/renderer/modules/mediasource/source_buffer_write_head.cc
@@ -0,0 +1,31 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "third_party/blink/renderer/modules/mediasource/source_buffer_write_head.h"
+
+#include "third_party/blink/renderer/modules/mediasource/source_buffer.h"
+#include "third_party/blink/renderer/platform/bindings/exception_state.h"
+
+#if !BUILDFLAG(USE_STARBOARD_MEDIA)
+#error "This file only works with Starboard media"
+#endif  // !BUILDFLAG(USE_STARBOARD_MEDIA)
+
+namespace blink {
+
+// static
+double SourceBufferWriteHead::writeHead(SourceBuffer& source_buffer,
+                                        ExceptionState& exception_state) {
+  return source_buffer.GetWriteHead(exception_state);
+}
+}  // namespace blink
diff --git a/third_party/blink/renderer/modules/mediasource/source_buffer_write_head.h b/third_party/blink/renderer/modules/mediasource/source_buffer_write_head.h
new file mode 100644
index 000000000000..e5a52110d793
--- /dev/null
+++ b/third_party/blink/renderer/modules/mediasource/source_buffer_write_head.h
@@ -0,0 +1,39 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASOURCE_SOURCE_BUFFER_WRITE_HEAD_H_
+#define THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASOURCE_SOURCE_BUFFER_WRITE_HEAD_H_
+
+#include "build/build_config.h"
+#include "third_party/blink/renderer/platform/wtf/allocator/allocator.h"
+
+#if !BUILDFLAG(USE_STARBOARD_MEDIA)
+#error "This file only works with Starboard media"
+#endif  // !BUILDFLAG(USE_STARBOARD_MEDIA)
+
+namespace blink {
+
+class ExceptionState;
+class SourceBuffer;
+
+class SourceBufferWriteHead {
+  STATIC_ONLY(SourceBufferWriteHead);
+
+ public:
+  static double writeHead(SourceBuffer&, ExceptionState&);
+};
+
+}  // namespace blink
+
+#endif  // THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASOURCE_SOURCE_BUFFER_WRITE_HEAD_H_
diff --git a/third_party/blink/renderer/modules/mediasource/source_buffer_write_head.idl b/third_party/blink/renderer/modules/mediasource/source_buffer_write_head.idl
new file mode 100644
index 000000000000..8ff5c972d000
--- /dev/null
+++ b/third_party/blink/renderer/modules/mediasource/source_buffer_write_head.idl
@@ -0,0 +1,24 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Non standard interface used for Cobalt only.
+// Returns the highest presentation timestamp written to the Renderer;
+// raises `InvalidStateError` if the SourceBuffer object has been removed
+// from the MediaSource object.
+
+[
+    ImplementedAs=SourceBufferWriteHead
+] partial interface SourceBuffer {
+    [RaisesException] readonly attribute double writeHead;
+};
\ No newline at end of file
diff --git a/third_party/blink/renderer/platform/media/web_source_buffer_impl.cc b/third_party/blink/renderer/platform/media/web_source_buffer_impl.cc
index a040298abd08..a3eb88f63b34 100644
--- a/third_party/blink/renderer/platform/media/web_source_buffer_impl.cc
+++ b/third_party/blink/renderer/platform/media/web_source_buffer_impl.cc
@@ -245,6 +245,14 @@ void WebSourceBufferImpl::RemovedFromMediaSource() {
   client_ = nullptr;
 }
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+double WebSourceBufferImpl::GetWriteHead(
+    ExceptionState& exception_state) const {
+  DCHECK(demuxer_);
+  return demuxer_->GetWriteHead(id_).InSecondsF();
+}
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
 WebMediaPlayer::TrackType mediaTrackTypeToBlink(media::MediaTrack::Type type) {
   switch (type) {
     case media::MediaTrack::Audio:
diff --git a/third_party/blink/renderer/platform/media/web_source_buffer_impl.h b/third_party/blink/renderer/platform/media/web_source_buffer_impl.h
index 5ecfab637271..25c272f8d1f5 100644
--- a/third_party/blink/renderer/platform/media/web_source_buffer_impl.h
+++ b/third_party/blink/renderer/platform/media/web_source_buffer_impl.h
@@ -24,6 +24,10 @@ enum class SourceBufferParseWarning;
 
 namespace blink {
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+class ExceptionState;
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
 class PLATFORM_EXPORT WebSourceBufferImpl : public WebSourceBuffer {
  public:
   WebSourceBufferImpl(const std::string& id, media::ChunkDemuxer* demuxer);
@@ -57,6 +61,11 @@ class PLATFORM_EXPORT WebSourceBufferImpl : public WebSourceBuffer {
   void SetAppendWindowEnd(double end) override;
   void RemovedFromMediaSource() override;
 
+#if BUILDFLAG(USE_STARBOARD_MEDIA)
+  // Return the highest presentation timestamp written to the Renderer.
+  double GetWriteHead(ExceptionState& exception_state) const override;
+#endif  // BUILDFLAG(USE_STARBOARD_MEDIA)
+
  private:
   // Demuxer callback handler to process an initialization segment received
   // during an append() call.
diff --git a/third_party/blink/renderer/platform/widget/compositing/layer_tree_settings.cc b/third_party/blink/renderer/platform/widget/compositing/layer_tree_settings.cc
index 3ebaee0026af..0a0888ceb3de 100644
--- a/third_party/blink/renderer/platform/widget/compositing/layer_tree_settings.cc
+++ b/third_party/blink/renderer/platform/widget/compositing/layer_tree_settings.cc
@@ -105,71 +105,16 @@ cc::ManagedMemoryPolicy GetGpuMemoryPolicy(
   }
 
 #if BUILDFLAG(IS_ANDROID)
-  // We can't query available GPU memory from the system on Android.
-  // Physical memory is also mis-reported sometimes (eg. Nexus 10 reports
-  // 1262MB when it actually has 2GB, while Razr M has 1GB but only reports
-  // 128MB java heap size). First we estimate physical memory using both.
-  size_t dalvik_mb = base::SysInfo::DalvikHeapSizeMB();
-  size_t physical_mb = base::SysInfo::AmountOfPhysicalMemoryMB();
-  size_t physical_memory_mb = 0;
-  if (base::SysInfo::IsLowEndDevice()) {
-    // TODO(crbug.com/742534): The code below appears to no longer work.
-    // |dalvik_mb| no longer follows the expected heuristic pattern, causing us
-    // to over-estimate memory on low-end devices. This entire section probably
-    // needs to be re-written, but for now we can address the low-end Android
-    // issues by ignoring |dalvik_mb|.
-    physical_memory_mb = physical_mb;
-  } else if (dalvik_mb >= 256) {
-    physical_memory_mb = dalvik_mb * 4;
+  if (base::SysInfo::IsLowEndDevice() ||
+      base::SysInfo::AmountOfPhysicalMemoryMB() < 2000) {
+    actual.bytes_limit_when_visible = 96 * 1024 * 1024;
   } else {
-    physical_memory_mb = std::max(dalvik_mb * 4, (physical_mb * 4) / 3);
+    actual.bytes_limit_when_visible = 256 * 1024 * 1024;
   }
-
-  // Now we take a default of 1/8th of memory on high-memory devices,
-  // and gradually scale that back for low-memory devices (to be nicer
-  // to other apps so they don't get killed). Examples:
-  // Nexus 4/10(2GB)    256MB (normally 128MB)
-  // Droid Razr M(1GB)  114MB (normally 57MB)
-  // Galaxy Nexus(1GB)  100MB (normally 50MB)
-  // Xoom(1GB)          100MB (normally 50MB)
-  // Nexus S(low-end)   8MB (normally 8MB)
-  // Note that the compositor now uses only some of this memory for
-  // pre-painting and uses the rest only for 'emergencies'.
-  if (actual.bytes_limit_when_visible == 0) {
-    // NOTE: Non-low-end devices use only 50% of these limits,
-    // except during 'emergencies' where 100% can be used.
-    if (physical_memory_mb >= 1536) {
-      actual.bytes_limit_when_visible = physical_memory_mb / 8;  // >192MB
-    } else if (physical_memory_mb >= 1152) {
-      actual.bytes_limit_when_visible = physical_memory_mb / 8;  // >144MB
-    } else if (physical_memory_mb >= 768) {
-      actual.bytes_limit_when_visible = physical_memory_mb / 10;  // >76MB
-    } else if (physical_memory_mb >= 513) {
-      actual.bytes_limit_when_visible = physical_memory_mb / 12;  // <64MB
-    } else {
-      // Devices with this little RAM have very little headroom so we hardcode
-      // the limit rather than relying on the heuristics above.  (They also use
-      // 4444 textures so we can use a lower limit.)
-      actual.bytes_limit_when_visible = 8;
-    }
-
-    actual.bytes_limit_when_visible =
-        actual.bytes_limit_when_visible * 1024 * 1024;
-    // Clamp the observed value to a specific range on Android.
-    actual.bytes_limit_when_visible = std::max(
-        actual.bytes_limit_when_visible, static_cast<size_t>(8 * 1024 * 1024));
-    actual.bytes_limit_when_visible =
-        std::min(actual.bytes_limit_when_visible,
-                 static_cast<size_t>(256 * 1024 * 1024));
-  }
-  actual.priority_cutoff_when_visible =
-      gpu::MemoryAllocation::CUTOFF_ALLOW_EVERYTHING;
 #else
   // Ignore what the system said and give all clients the same maximum
   // allocation on desktop platforms.
   actual.bytes_limit_when_visible = 512 * 1024 * 1024;
-  actual.priority_cutoff_when_visible =
-      gpu::MemoryAllocation::CUTOFF_ALLOW_NICE_TO_HAVE;
 
   // For large monitors (4k), double the tile memory to avoid frequent out of
   // memory problems. 4k could mean a screen width of anywhere from 3840 to 4096
@@ -181,6 +126,9 @@ cc::ManagedMemoryPolicy GetGpuMemoryPolicy(
   if (display_width >= kLargeDisplayThreshold)
     actual.bytes_limit_when_visible *= 2;
 #endif
+  actual.priority_cutoff_when_visible =
+      gpu::MemoryAllocation::CUTOFF_ALLOW_NICE_TO_HAVE;
+
   return actual;
 }
 
diff --git a/third_party/blink/web_tests/external/wpt/cobalt/crash-annotator/README.md b/third_party/blink/web_tests/external/wpt/cobalt/crash-annotator/README.md
new file mode 100644
index 000000000000..cd1c51ca4972
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/cobalt/crash-annotator/README.md
@@ -0,0 +1,6 @@
+# Web tests for CrashAnnotator
+
+These automated tests rely on a test-only interface that must be provided by the
+browser under test. The pattern from the Serial API is followed: an
+implementation of the CrashAnnotator Mojo interface is provided by
+`../../resources/chromium/cobalt/fake-crash-annotator.js`.
diff --git a/third_party/blink/web_tests/external/wpt/cobalt/crash-annotator/crash_annotator_setString.https.any.js b/third_party/blink/web_tests/external/wpt/cobalt/crash-annotator/crash_annotator_setString.https.any.js
new file mode 100644
index 000000000000..21fba8cdd5ae
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/cobalt/crash-annotator/crash_annotator_setString.https.any.js
@@ -0,0 +1,18 @@
+// META: global=window
+// META: script=/resources/test-only-api.js
+// META: script=resources/automation.js
+
+crash_annotator_test(async (t, fake) => {
+  let expectedSetStringResult = true;
+  fake.stubResult(expectedSetStringResult);
+  let setStringResult =
+      await navigator.crashAnnotator.setString("some key", "some val");
+  assert_equals(setStringResult, expectedSetStringResult);
+}, 'setString() returns value provided by browser endpoint');
+
+crash_annotator_test(async (t, fake) => {
+  let key = "some key";
+  let value = "some value";
+  await navigator.crashAnnotator.setString(key, value);
+  assert_equals(fake.getAnnotation(key), value);
+}, 'setString() sends expected key and value to browser endpoint');
diff --git a/third_party/blink/web_tests/external/wpt/cobalt/crash-annotator/resources/automation.js b/third_party/blink/web_tests/external/wpt/cobalt/crash-annotator/resources/automation.js
new file mode 100644
index 000000000000..c630f663ca58
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/cobalt/crash-annotator/resources/automation.js
@@ -0,0 +1,26 @@
+'use strict';
+
+// These tests use a fake implementation of the CrashAnnotator Mojo interface.
+
+let fakeCrashAnnotator = undefined;
+
+function crash_annotator_test(func, name, properties) {
+  promise_test(async (test) => {
+    assert_implements(navigator.crashAnnotator,
+                      'missing navigator.crashAnnotator');
+    if (fakeCrashAnnotator === undefined) {
+      const fakes =
+          await import('/resources/chromium/cobalt/fake-crash-annotator.js');
+      fakeCrashAnnotator = fakes.fakeCrashAnnotator;
+    }
+    assert_implements(fakeCrashAnnotator, 'missing fakeCrashAnnotator');
+
+    fakeCrashAnnotator.start();
+    try {
+      await func(test, fakeCrashAnnotator);
+    } finally {
+      fakeCrashAnnotator.stop();
+      fakeCrashAnnotator.reset();
+    }
+    }, name, properties);
+  }
diff --git a/third_party/blink/web_tests/external/wpt/media-source/SourceBuffer-writeHead.html b/third_party/blink/web_tests/external/wpt/media-source/SourceBuffer-writeHead.html
new file mode 100644
index 000000000000..56b93e84c945
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/media-source/SourceBuffer-writeHead.html
@@ -0,0 +1,102 @@
+<!doctype html>
+<html>
+
+<head>
+    <title>SourceBuffer.writeHead test cases</title>
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="mediasource-util.js"></script>
+</head>
+
+<body>
+    <div id="log"></div>
+    <script>
+        // TODO: b/388319612 - Cobalt: Add adaptive formats to mediasource-util.js.
+        function sourcebuffer_writehead_test(testFunction, description, options, useSegmentsMode) {
+            mediasource_testafterdataloaded(function (test, mediaElement, mediaSource, segmentInfo, sourceBuffer, mediaData) {
+                if (useSegmentsMode) {
+                    sourceBuffer.mode = "segments";
+                }
+                mediaElement.addEventListener("error", test.unreached_func("Unexpected event 'error'"));
+                testFunction(test, segmentInfo, sourceBuffer, mediaData);
+            }, description, options);
+        }
+
+        function append_initial_segment(test, sourceBuffer, segmentInfo, mediaData, callback) {
+            let segment = MediaSourceUtil.extractSegmentData(mediaData, segmentInfo.init);
+            test.expectEvent(sourceBuffer, "updateend", "segment append ended.");
+            sourceBuffer.appendBuffer(segment);
+            test.waitForExpectedEvents(callback);
+        }
+
+        function append_segment(test, sourceBuffer, segmentInfo, mediaData, index, callback) {
+            if (index >= segmentInfo.media.length) {
+                callback();
+                return;
+            }
+            let mediaSegment = MediaSourceUtil.extractSegmentData(mediaData, segmentInfo.media[index]);
+            test.expectEvent(sourceBuffer, "updateend", "media segment append ended.");
+            sourceBuffer.appendBuffer(mediaSegment);
+            test.waitForExpectedEvents(callback);
+        }
+
+        sourcebuffer_writehead_test(function (test, segmentInfo, sourceBuffer, mediaData) {
+            let index = 0;
+            // Write and check that the writeHead updates to the correct end timestamp for all segments.
+            function write_and_check_all_segments() {
+                append_segment(test, sourceBuffer, segmentInfo, mediaData, index, function () {
+                    assert_equals(sourceBuffer.writeHead, segmentInfo.media[index].endtimea);
+                    index = index + 1;
+                    if (index >= segmentInfo.media.length) {
+                        test.done();
+                        return;
+                    }
+                    write_and_check_all_segments();
+                });
+            };
+
+            // writeHead should be 0 with no data appended.
+            assert_equals(sourceBuffer.writeHead, 0);
+            append_initial_segment(test, sourceBuffer, segmentInfo, mediaData, function () {
+                // The initial writeHead to match the start time of the next buffer.
+                assert_equals(sourceBuffer.writeHead, segmentInfo.media[0].timea);
+                write_and_check_all_segments();
+            });
+        }, "Append and check all segments in sequence mode", {}, false);
+
+        sourcebuffer_writehead_test(function (test, segmentInfo, sourceBuffer, mediaData) {
+            // Append all segments in reverse order, after the initial segment.
+            let index = segmentInfo.media.length - 1;
+            // Stores the running expected writeHead by summing the durations of appended segments.
+            let expectedWriteHead = 0;
+            function write_and_check_all_segments() {
+                append_segment(test, sourceBuffer, segmentInfo, mediaData, index, function () {
+                    let segmentLength = segmentInfo.media[index].endtimea - segmentInfo.media[index].timea;
+                    expectedWriteHead = expectedWriteHead + segmentLength;
+                    assert_equals(sourceBuffer.writeHead, expectedWriteHead);
+                    index = index - 1;
+                    if (index <= 0) {
+                        test.done();
+                        return;
+                    }
+                    write_and_check_all_segments();
+                });
+            };
+
+            assert_equals(sourceBuffer.writeHead, 0);
+            append_initial_segment(test, sourceBuffer, segmentInfo, mediaData, function () {
+                assert_equals(sourceBuffer.writeHead, segmentInfo.media[0].timea);
+                expectedWriteHead = segmentInfo.media[0].timea;
+                write_and_check_all_segments();
+            });
+        }, "Append and check all segments in reverse order in segments mode", {}, true);
+
+        sourcebuffer_writehead_test(function (test, segmentInfo, sourceBuffer, mediaData) {
+            assert_equals(sourceBuffer.writeHead, 0);
+            test.done();
+        }, "No data appended", {}, false);
+
+    </script>
+</body>
+
+</html>
diff --git a/third_party/blink/web_tests/external/wpt/resources/chromium/cobalt/fake-crash-annotator.js b/third_party/blink/web_tests/external/wpt/resources/chromium/cobalt/fake-crash-annotator.js
new file mode 100644
index 000000000000..484bcb57bf36
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/resources/chromium/cobalt/fake-crash-annotator.js
@@ -0,0 +1,50 @@
+import {CrashAnnotator, CrashAnnotatorReceiver} from '/gen/third_party/blink/public/mojom/cobalt/crash_annotator/crash_annotator.mojom.m.js';
+
+// Implementation of blink.mojom.CrashAnnotator.
+class FakeCrashAnnotator {
+  constructor() {
+    this.interceptor_ =
+        new MojoInterfaceInterceptor(CrashAnnotator.$interfaceName);
+    this.interceptor_.oninterfacerequest = e => this.bind(e.handle);
+    this.receiver_ = new CrashAnnotatorReceiver(this);
+    this.stub_result_ = null;
+    this.annotations_ = new Map();
+  }
+
+  start() {
+    this.interceptor_.start();
+  }
+
+  stop() {
+    this.interceptor_.stop();
+  }
+
+  reset() {
+    this.stub_result_ = null;
+    this.annotations_ = new Map();
+  }
+
+  async setString(key, value) {
+    this.annotations_.set(key, value);
+    return {
+      result: this.stub_result_
+    };
+  }
+
+  // Added for stubbing setString() result in tests.
+  stubResult(stub_result) {
+    this.stub_result_ = stub_result;
+  }
+
+  // Added for testing setString() interactions.
+  getAnnotation(key) {
+    return this.annotations_.get(key);
+  }
+
+  bind(handle) {
+    this.receiver_.$.bindHandle(handle);
+  }
+
+}
+
+export const fakeCrashAnnotator = new FakeCrashAnnotator();