Extend "window open steps" to observe COOP

Specify that window.open() and document.open() must return null when
COOP restrictions are being enforced.

Closes #5759.

Author: jugglinmike

source

@@ -23313,9 +23313,9 @@ document.body.appendChild(wbr);</code></pre>
    an element's noopener</span> with <var>subject</var> and
    <var>targetAttributeValue</var>.</p></li>
 
-   <li><p>Let <var>target</var> and <var>replace</var> be the result of applying <span>the rules for
-   choosing a browsing context</span> given <var>targetAttributeValue</var>, <var>source</var>, and
-   <var>noopener</var>.</p></li>
+   <li><p>Let <var>target</var> and <var>windowType</var> be the result of applying <span>the rules
+   for choosing a browsing context</span> given <var>targetAttributeValue</var>, <var>source</var>,
+   and <var>noopener</var>.</p></li>
 
    <li><p>If <var>target</var> is null, then return.</p></li>
 
@@ -23348,9 +23348,9 @@ document.body.appendChild(wbr);</code></pre>
 
    <li><p><span>Queue an element task</span> on the <span>DOM manipulation task source</span> given
    <var>subject</var> to <span>navigate</span><!--DONAV hyperlink--> the <var>target</var>
-   <span>browsing context</span> to <var>request</var>. If <var>replace</var> is true, the
-   navigation must be performed with <span>replacement enabled</span>. The <span>source browsing
-   context</span> must be <var>source</var>.</p></li>
+   <span>browsing context</span> to <var>request</var>. If <var>windowType</var> is not "<code
+   data-x="">existing or none</code>", the navigation must be performed with <span>replacement
+   enabled</span>. The <span>source browsing context</span> must be <var>source</var>.</p></li>
   </ol>
 
   </div>
@@ -55687,9 +55687,13 @@ fur
    <li><p>Let <var>noopener</var> be the result of <span data-x="get an element's noopener">getting
    an element's noopener</span> with <var>form</var> and <var>targetAttributeValue</var>.</p></li>
 
-   <li><p>Let <var>target browsing context</var> and <var>replace</var> be the result of applying
-   <span>the rules for choosing a browsing context</span> using <var>target</var>, <var>form
-   browsing context</var>, and <var>noopener</var>.</p></li>
+   <li><p>Let <var>target browsing context</var> and <var>windowType</var> be the result of
+   applying <span>the rules for choosing a browsing context</span> using <var>target</var>,
+   <var>form browsing context</var>, and <var>noopener</var>.</p></li>
+
+   <li><p>Let <var>replace</var> be true if <var>windowType</var> is either "<code
+   data-x="">new and unrestricted</code>" or "<code data-x="">new with no opener</code>", and false
+   otherwise.</p></li>
 
    <li><p>If <var>target browsing context</var> is null, then return.</p></li>
 
@@ -77720,7 +77724,7 @@ console.assert(iframeWindow.frameElement === null);
   <ol>
    <li><p>Let <var>chosen</var> be null.</p></li>
 
-   <li><p>Let <var>new</var> be false.</p></li>
+   <li><p>Let <var>windowType</var> be "<code data-x="">existing or none</code>".</p></li>
 
    <li><p>Let <var>sandboxingFlagSet</var> be <var>current</var>'s <span>active document</span>'s
    <span>active sandboxing flag set</span>.</p></li>
@@ -77770,7 +77774,8 @@ console.assert(iframeWindow.frameElement === null);
 
       <ol>
        <li><p>Set <var>chosen</var> to the result of <span>creating a new top-level browsing
-       context</span> and set <var>new</var> to true.</p></li>
+       context</span> and set <var>windowType</var> to "<code data-x="">new and
+       unrestricted</code>".</p></li>
 
        <li><p>Set <var>chosen</var> to an existing <span>top-level browsing context</span>.</p>
       </ol>
@@ -77787,6 +77792,8 @@ console.assert(iframeWindow.frameElement === null);
 
      <dd>
       <ol>
+       <li><p>Set <var>windowType</var> to "<code data-x="">new and unrestricted</code>".</p></li>
+
        <li>
         <p>If <var>current</var>'s <span>top-level browsing context</span>'s <span>active
         document</span>'s <span data-x="concept-document-coop">cross-origin opener policy</span> is
@@ -77800,8 +77807,9 @@ console.assert(iframeWindow.frameElement === null);
          <li>
           <p>If <var>currentDocument</var>'s <span>origin</span> is not <span>same origin</span>
           with <var>currentDocument</var>'s <span>relevant settings object</span>'s <span>top-level
-          origin</span>, then set <var>noopener</var> to true and <var>name</var> to "<code
-          data-x="">_blank</code>".</p>
+          origin</span>, then set <var>noopener</var> to true, <var>name</var> to "<code
+          data-x="">_blank</code>", and <var>windowType</var> to "<code data-x="">new with no
+          opener</code>".</p>
 
           <p class="note">In the presence of a <span>cross-origin opener policy</span>, nested
           documents that are cross-origin with their top-level browsing context's active document
@@ -77810,7 +77818,6 @@ console.assert(iframeWindow.frameElement === null);
         </ol>
        </li>
 
-       <li><p>Set <var>new</var> to true.</p></li>
 
        <li id="noopener"><p>If <var>noopener</var> is true, then set <var>chosen</var> to the result
        of <span>creating a new top-level browsing context</span>.</p></li>
@@ -77857,7 +77864,7 @@ console.assert(iframeWindow.frameElement === null);
     agent to always reuse <var>current</var>.</p>
    </li>
 
-   <li><p>Return <var>chosen</var> and <var>new</var>.</p></li>
+   <li><p>Return <var>chosen</var> and <var>windowType</var>.</p></li>
   </ol>
 
 
@@ -78390,9 +78397,9 @@ dictionary <dfn>WindowPostMessageOptions</dfn> : <span>PostMessageOptions</span>
    <li><p>If <var>noreferrer</var> is true, then set <var>noopener</var> to true.</p></li>
 
    <li>
-    <p>Let <var>target browsing context</var> and <var>new</var> be the result of applying <span>the
-    rules for choosing a browsing context</span> given <var>target</var>, <var>source browsing
-    context</var>, and <var>noopener</var>.</p>
+    <p>Let <var>target browsing context</var> and <var>windowType</var> be the result of applying
+    <span>the rules for choosing a browsing context</span> given <var>target</var>, <var>source
+    browsing context</var>, and <var>noopener</var>.</p>
 
     <p class="example">If there is a user agent that supports control-clicking a link to open it in
     a new tab, and the user control-clicks on an element whose <code
@@ -78402,6 +78409,9 @@ dictionary <dfn>WindowPostMessageOptions</dfn> : <span>PostMessageOptions</span>
     tab.</p>
    </li>
 
+   <li><p>Let <var>new</var> be true if <var>windowType</var> is either "<code data-x="">new and
+   unrestricted</code>" or "<code data-x="">new with no opener</code>", and false otherwise.</p></li>
+
    <li><p>If <var>target browsing context</var> is null, then return null.</p></li>
 
    <li><p>If <var>new</var> is true, then <span>set up browsing context features</span> for
@@ -78443,7 +78453,8 @@ dictionary <dfn>WindowPostMessageOptions</dfn> : <span>PostMessageOptions</span>
     </ol>
    </li>
 
-   <li><p>If <var>noopener</var> is true, then return null.</p></li>
+   <li><p>If <var>noopener</var> is true or <var>windowType</var> is "<code
+   data-x="">new with no opener</code>", then return null.</p></li>
 
    <li>
     <p>Otherwise, if <var>new</var> is false, set <var>target browsing context</var>'s <span>opener