Populate document state origin/initiator origin upon creation

This fixes #9460 by supplying an initiator origin (or explicitly null) everywhere we create a new document state.

source

@@ -93226,6 +93226,13 @@ interface <dfn interface>BeforeUnloadEvent</dfn> : <span>Event</span> {
      <dt><span data-x="document-state-document">document</span></dt>
      <dd><var>document</var></dd>
 
+     <dt><span data-x="document-state-initiator-origin">initiator origin</span></dt>
+     <dd>null if <var>opener</var> is null; otherwise, <var>document</var>'s <span
+     data-x="concept-document-origin">origin</span></dd>
+
+     <dt><span data-x="document-state-origin">origin</span></dt>
+     <dd><var>document</var>'s <span data-x="concept-document-origin">origin</span></dd>
+
      <dt><span data-x="document-state-nav-target-name">navigable target name</span></dt>
      <dd><var>targetName</var></dd>
 
@@ -93392,6 +93399,12 @@ interface <dfn interface>BeforeUnloadEvent</dfn> : <span>Event</span> {
      <dt><span data-x="document-state-document">document</span></dt>
      <dd><var>document</var></dd>
 
+     <dt><span data-x="document-state-initiator-origin">initiator origin</span></dt>
+     <dd><var>document</var>'s <span data-x="concept-document-origin">origin</span></dd>
+
+     <dt><span data-x="document-state-origin">origin</span></dt>
+     <dd><var>document</var>'s <span data-x="concept-document-origin">origin</span></dd>
+
      <dt><span data-x="document-state-nav-target-name">navigable target name</span></dt>
      <dd><var>targetName</var></dd>
 
@@ -96342,6 +96355,9 @@ location.href = '#foo';</code></pre>
     <code>Document</code> was created, so we will not perform a navigation.</p>
    </li>
 
+   <li><p><span>Assert</span>: <var>initiatorOrigin</var> is <var>newDocument</var>'s <span
+   data-x="concept-document-origin">origin</span>.</p></li>
+
    <li><p>Let <var>entryToReplace</var> be <var>targetNavigable</var>'s <span
    data-x="nav-active-history-entry">active session history entry</span>.</p></li>
 
@@ -96369,8 +96385,11 @@ location.href = '#foo';</code></pre>
      referrer policy</span> <span class="XXX">or should this be the <var>referrerPolicy</var> that
      was passed to <span>navigate</span>?</span></dd>
 
-     <dt><span data-x="document-state-initiator-origin">origin</span></dt>
-     <dd><var>initiatorOriginSnapshot</var></dd>
+     <dt><span data-x="document-state-initiator-origin">initiator origin</span></dt>
+     <dd><var>initiatorOrigin</var></dd>
+
+     <dt><span data-x="document-state-origin">origin</span></dt>
+     <dd><var>initiatorOrigin</var></dd>
 
      <dt><span data-x="document-state-about-base-url">about base URL</span></dt>
      <dd><var>oldDocState</var>'s <span data-x="document-state-about-base-url">about base
@@ -98252,6 +98271,10 @@ location.href = '#foo';</code></pre>
        <dd><var>oldDocState</var>'s <span data-x="document-state-request-referrer-policy">request
        referrer policy</span></dd>
 
+       <dt><span data-x="document-state-initiator-origin">initiator origin</span></dt>
+       <dd><var>oldDocState</var>'s <span data-x="document-state-initiator-origin">initiator
+       origin</span></dd>
+
        <dt><span data-x="document-state-origin">origin</span></dt>
        <dd><var>oldDocState</var>'s <span data-x="document-state-origin">origin</span></dd>