[ci] Split build_all_packages by JDK version. (#7106)

This PR introduces a new `android_build_all_packages_legacy` in `master`
and `stable` to build only the "legacy" version of an Android project
using JDK11.

This PR is required to resume rolling the flutter framework, like here:

* #7099

.ci.yaml

@@ -376,12 +376,38 @@ targets:
           "CHANNEL": "master"
         }
 
+  - name: Linux_android android_build_all_packages_legacy master
+    # When making this `bringup: false`, update the task above to
+    # use target_file: android_build_all_packages_jdk17.yaml and
+    # remove its 'dependencies' section.
+    bringup: true # https://github.com/flutter/packages/pull/7099
+    recipe: packages/packages
+    timeout: 30
+    properties:
+      version_file: flutter_master.version
+      # TODO(stuartmorgan): Once stable requires JDK 17, and the
+      # legacy project is updated accordingly, this entire target
+      # can be merged back into android_build_all_packages.
+      # This file only builds a *legacy* version of the project.
+      target_file: android_build_all_packages_legacy.yaml
+      channel: master
+      # The legacy project build requires an older JDK.
+      dependencies: >-
+        [
+          {"dependency": "open_jdk", "version": "version:11"}
+        ]
+      env_variables: >-
+        {
+          "CHANNEL": "master"
+        }
+
   - name: Linux_android android_build_all_packages stable
     recipe: packages/packages
     timeout: 30
     properties:
       add_recipes_cq: "true"
       version_file: flutter_stable.version
+      # This builds both legacy, and "modern" projects.
       target_file: android_build_all_packages.yaml
       channel: stable
       # The legacy project build requires an older JDK.
@@ -394,6 +420,28 @@ targets:
           "CHANNEL": "stable"
         }
 
+  - name: Linux_android android_build_all_packages_legacy stable
+    # When making this `bringup: false`, update the task above to
+    # use target_file: android_build_all_packages_jdk17.yaml and
+    # remove its 'dependencies' section.
+    bringup: true # https://github.com/flutter/packages/pull/7099
+    recipe: packages/packages
+    timeout: 30
+    properties:
+      version_file: flutter_stable.version
+      # This file only builds a *legacy* version of the project.
+      target_file: android_build_all_packages_legacy.yaml
+      channel: stable
+      # The legacy project build requires an older JDK.
+      dependencies: >-
+        [
+          {"dependency": "open_jdk", "version": "version:11"}
+        ]
+      env_variables: >-
+        {
+          "CHANNEL": "stable"
+        }
+
   - name: Linux_android android_platform_tests_shard_1 master
     recipe: packages/packages
     timeout: 60

.ci/targets/android_build_all_packages.yaml

@@ -1,3 +1,5 @@
+# This builds legacy and modern all_packages app, which requires jdk11
+# This will stop working in the next stable!
 tasks:
   - name: prepare tool
     script: .ci/scripts/prepare_tool.sh

.ci/targets/android_build_all_packages_jdk17.yaml

@@ -0,0 +1,14 @@
+# This only builds the modern all_packages app, which requires jdk17+
+tasks:
+  - name: prepare tool
+    script: .ci/scripts/prepare_tool.sh
+    infra_step: true # Note infra steps failing prevents "always" from running.
+  - name: create all_packages app
+    script: .ci/scripts/create_all_packages_app.sh
+    infra_step: true # Note infra steps failing prevents "always" from running.
+  - name: build all_packages for Android debug
+    script: .ci/scripts/build_all_packages_app.sh
+    args: ["apk", "debug"]
+  - name: build all_packages for Android release
+    script: .ci/scripts/build_all_packages_app.sh
+    args: ["apk", "release"]

.ci/targets/android_build_all_packages_legacy.yaml

@@ -0,0 +1,17 @@
+# This only builds the legacy all_packages app, which requires jdk11
+tasks:
+  - name: prepare tool
+    script: .ci/scripts/prepare_tool.sh
+    infra_step: true # Note infra steps failing prevents "always" from running.
+  - name: create all_packages app - legacy version
+    script: .ci/scripts/create_all_packages_app_legacy.sh
+    # Output dir; must match the final argument to build_all_packages_app_legacy
+    # below.
+    args: ["legacy"]
+  # Only build legacy in one mode, to minimize extra CI time. Debug is chosen
+  # somewhat arbitrarily as likely being slightly faster.
+  - name: build all_packages for Android - legacy version
+    script: .ci/scripts/build_all_packages_app_legacy.sh
+    # The final argument here must match the output directory passed to
+    # create_all_packages_app_legacy above.
+    args: ["apk", "debug", "legacy"]