Raise "no such window" error in "dispatch tick actions" when browsing context (navigable) does no longer exist

Author: whimboo

index.html

@@ -9223,6 +9223,9 @@ <h3>Dispatching actions</h3>
  <li><p>For each <var>action object</var> in <var>tick actions</var>:
 
   <ol>
+   <li>If <var>browsing context</var> is <a>no longer open</a>, return
+    <a>error</a> with <a>error code</a> <a>no such window</a>.
+
    <li><p>Let <var>input id</var> be equal to the value
     of <var>action object</var>&apos;s id property.