Revise event listener removal in document.open()

This change aligns the event listener removal behavior with
implementations, specifically in two aspects:

- The event handler's value should be set to null (i.e., deactivated).
- Event listeners and handlers should be removed from the Window object
  as well.

See prior investigation around deactivation of event handlers in whatwg#3836
and whatwg#3850. See investigation around document.open()'s behavior in
whatwg#3818.

Tests: web-platform-tests/wpt#12122

source

@@ -89947,8 +89947,7 @@ dictionary <dfn>PromiseRejectionEventInit</dfn> : <span>EventInit</span> {
 
   <p>To <dfn>deactivate an event handler</dfn> given an <code>EventTarget</code> object
   <var>eventTarget</var> and a string <var>name</var> that is the <span data-x="event handler
-  name">name</span> of an <span data-x="event handlers">event handler</span>, take the following
-  steps:</p>
+  name">name</span> of an <span data-x="event handlers">event handler</span>, run these steps:</p>
 
   <ol>
    <li><p>Let <var>handlerMap</var> be <var>eventTarget</var>'s <span>event handler
@@ -89969,10 +89968,24 @@ dictionary <dfn>PromiseRejectionEventInit</dfn> : <span>EventInit</span> {
    null.</p></li>
   </ol>
 
+  <p>To <dfn>erase all event listeners and handlers</dfn> given an <code>EventTarget</code> object
+  <var>eventTarget</var>, run these steps:</p>
+
+  <ol>
+   <li><p>If <var>eventTarget</var> has an associated <span>event handler map</span>, then for each
+   <var>name</var> → <var>eventHandler</var> of <var>eventTarget</var>'s associated <span>event
+   handler map</span>, <span>deactivate an event handler</span> given <var>eventTarget</var> and
+   <var>name</var>.</p></li>
+
+   <li><p><span>Remove all event listeners</span> given <var>eventTarget</var>.</p></li>
+  </ol>
+
+  <p class="note">This algorithm is used to define <code
+  data-x="dom-document-open">document.open(<var>type</var>, <var>replace</var>)</code>.</p>
+
   <p>To <dfn>activate an event handler</dfn> given an <code>EventTarget</code> object
   <var>eventTarget</var> and a string <var>name</var> that is the <span data-x="event handler
-  name">name</span> of an <span data-x="event handlers">event handler</span>, take the following
-  steps:</p>
+  name">name</span> of an <span data-x="event handlers">event handler</span>, run these steps:</p>
 
   <ol>
    <li><p>Let <var>handlerMap</var> be <var>eventTarget</var>'s <span>event handler
@@ -90987,6 +91000,9 @@ document.body.appendChild(frame)</code></pre>
    <li><p>If <var>document</var> is not an <span>active document</span>, then return
    <var>document</var>.</p></li>
 
+   <li><p>Let <var>window</var> be <var>document</var>'s <span
+   data-x="concept-relevant-global">relevant global object</span>.</p></li>
+
    <li><p>If <var>document</var>'s <span>origin</span> is not <span>same origin</span> to the
    <span>origin</span> of the <span>responsible document</span> specified by the <span>entry
    settings object</span>, then throw a <span>"<code>SecurityError</code>"</span>
@@ -91041,7 +91057,10 @@ document.body.appendChild(frame)</code></pre>
    <li><p><span data-x="abort a document">Abort</span> <var>document</var>.</p></li>
 
    <li><p>For each <span>shadow-including inclusive descendant</span> <var>node</var> of
-   <var>document</var>, <span>remove all event listeners</span> with <var>node</var>.</p></li>
+   <var>document</var>, <span>erase all event listeners and handlers</span> given
+   <var>node</var>.</p></li>
+
+   <li><p><span>Erase all event listeners and handlers</span> given <var>window</var>.</p></li>
 
    <li><p>Remove any <span data-x="concept-task">tasks</span> associated with <var>document</var> in
    any <span>task source</span>.</p></li>
@@ -91056,8 +91075,8 @@ document.body.appendChild(frame)</code></pre>
     realm</span> with the following customizations:</p>
 
     <ul>
-     <li><p>For the global object, create a new <code>Window</code> object
-     <var>window</var>.</p></li>
+     <li><p>For the global object, create a new <code>Window</code> object and set
+     <var>window</var> to it.</p></li>
 
      <li><p>For the global <b>this</b> binding, use <var>document</var>'s <span>browsing
      context</span>'s associated <code>WindowProxy</code>.</p></li>