Allow top layer elements to be nested within popovers

This allows top layer elements, including the dialog element, to be nested inside of an open popover, by not closing the popover when the new top layer element is opened. Without this patch, opening a modal dialog inside of a popover will make the page inert and make the dialog invisible.

Fixes whatwg#9998. See also whatwg/fullscreen#237.

Author: josepharhar

source

@@ -61386,8 +61386,14 @@ interface <dfn interface>HTMLDialogElement</dfn> : <span>HTMLElement</span> {
    <li><p>Set <span>this</span>'s <span>previously focused element</span> to the
    <span>focused</span> element.</p></li>
 
-   <li><p>Run <span>hide all popovers</span> given <span>this</span>'s <span>node
-   document</span>.</p></li>
+   <li><p>Let <var>hideUntil</var> be the result of running <span>topmost popover ancestor</span>
+   given <span>this</span>, null, and false.</p></li>
+
+   <li><p>If <var>hideUntil</var> is null, then set <var>hideUntil</var> to <span>this</span>'s
+   <span>node document</span>.</p></li>
+
+   <li><p>Run <span data-x="hide-all-popovers-until">hide all popovers until</span> given
+   <var>hideUntil</var>, false, and true.</p></li>
 
    <li><p>Run the <span>dialog focusing steps</span> given <span>this</span>.</p></li>
   </ol>
@@ -61449,8 +61455,14 @@ interface <dfn interface>HTMLDialogElement</dfn> : <span>HTMLElement</span> {
    <li><p>Set <span>this</span>'s <span>previously focused element</span> to the
    <span>focused</span> element.</p></li>
 
-   <li><p>Run <span>hide all popovers</span> given <span>this</span>'s <span>node
-   document</span>.</p></li>
+   <li><p>Let <var>hideUntil</var> be the result of running <span>topmost popover ancestor</span>
+   given <span>this</span>, null, and false.</p></li>
+
+   <li><p>If <var>hideUntil</var> is null, then set <var>hideUntil</var> to <span>this</span>'s
+   <span>node document</span>.</p></li>
+
+   <li><p>Run <span data-x="hide-all-popovers-until">hide all popovers until</span> given
+   <var>hideUntil</var>, false, and true.</p></li>
 
    <li><p>Run the <span>dialog focusing steps</span> given <span>this</span>.</p></li>
   </ol>
@@ -84925,7 +84937,7 @@ dictionary <dfn dictionary>DragEventInit</dfn> : <span>MouseEventInit</span> {
      data-x="attr-popover">popover</code> attribute.</p></li>
 
      <li><p>Let <var>ancestor</var> be the result of running the <span>topmost popover
-     ancestor</span> algorithm given <var>element</var> and <var>invoker</var>.</p></li>
+     ancestor</span> algorithm given <var>element</var>, <var>invoker</var>, and true.</p></li>
 
      <li><p>If <var>ancestor</var> is null, then set <var>ancestor</var> to
      <var>document</var>.</p></li>
@@ -85198,7 +85210,7 @@ dictionary <dfn dictionary>DragEventInit</dfn> : <span>MouseEventInit</span> {
    data-x="popover-showing-state">showing</span>; otherwise false.</p></li>
   </ol>
 
-  <p>To <dfn data-x="hide-all-popovers-until">hide all popovers until</dfn>, given an <span
+  <p>To <dfn export data-x="hide-all-popovers-until">hide all popovers until</dfn>, given an <span
   data-x="HTML elements">HTML element</span> or <code>Document</code> <var>endpoint</var>, a boolean
   <var>focusPreviousElement</var>, and a boolean <var>fireEvents</var>:</p>
 
@@ -85290,21 +85302,17 @@ dictionary <dfn dictionary>DragEventInit</dfn> : <span>MouseEventInit</span> {
   happens. For example, during light-dismiss of a popover, this algorithm ensures that we close only
   the popovers that aren't related to the node clicked by the user.</p>
 
-  <p>To <dfn export>hide all popovers</dfn>, given a <code>Document</code> <var>document</var>, run
-  <span data-x="hide-all-popovers-until">hide all popovers until</span> given <var>document</var>,
-  false, and false.</p>
-
-  <p>To find the <dfn>topmost popover ancestor</dfn>, given a <code>Node</code>
-  <var>newPopover</var>, and an <span data-x="HTML elements">HTML element</span> or null
-  <var>invoker</var>, perform the following steps. They return an <span data-x="HTML
-  elements">HTML element</span> or null.</p>
+  <p>To find the <dfn export>topmost popover ancestor</dfn>, given a <code>Node</code>
+  <var>newPopoverOrTopLayerElement</var>, an <span data-x="HTML elements">HTML element</span> or
+  null <var>invoker</var>, and a boolean <var>isPopover</var>, perform the following steps. They
+  return an <span data-x="HTML elements">HTML element</span> or null.</p>
 
   <div class="note">
    <p>The <span>topmost popover ancestor</span> algorithm will return the topmost (latest in the
-   <span>showing auto popover list</span>) ancestor popover for the provided popover. Popovers can
-   be related to each other in several ways, creating a tree of popovers. There are two paths
-   through which one popover (call it the "child" popover) can have a topmost ancestor popover (call
-   it the "parent" popover):</p>
+   <span>showing auto popover list</span>) ancestor popover for the provided popover or top layer
+   element. Popovers can be related to each other in several ways, creating a tree of popovers.
+   There are two paths through which one popover (call it the "child" popover) can have a topmost
+   ancestor popover (call it the "parent" popover):</p>
 
    <ol>
     <li><p>The popovers are nested within each other in the node tree. In this case, the descendant
@@ -85322,14 +85330,45 @@ dictionary <dfn dictionary>DragEventInit</dfn> : <span>MouseEventInit</span> {
    containing an invoking element that points back to the containing popover), and it allows for the
    construction of a well-formed tree from the (possibly cyclic) graph of connections. Only <span
    data-x="attr-popover-auto-state">auto</span> popovers are considered.</p>
+
+   <p>If the provided element is a top layer element such as a <code>dialog</code> which is not
+   showing as a popover, then <span>topmost popover ancestor</span> will only look in the node tree
+   to find the first popover.</p>
   </div>
 
   <ol>
+   <li>
+    <p>If <var>isPopover</var> is true:</p>
+
+    <ol>
+     <li><p><span>Assert</span>: <var>newPopoverOrTopLayerElement</var> is an <span data-x="HTML
+     elements">HTML element</span>.</p></li>
+
+     <li><p><span>Assert</span>: <var>newPopoverOrTopLayerElement</var>'s <code
+     data-x="attr-popover">popover</code> attribute is not in the <span
+     data-x="attr-popover-none-state">no popover state</span> or the <span
+     data-x="attr-popover-manual-state">manual</span> state.</p></li>
+
+     <li><p><span>Assert</span>: <var>newPopoverOrTopLayerElement</var>'s <span>popover visibility
+     state</span> is not in the <span data-x="popover-showing-state">popover showing
+     state</span>.</p></li>
+    </ol>
+   </li>
+
+   <li>
+    <p>Otherwise:</p>
+
+    <ol>
+     <li><p><span>Assert</span>: <var>invoker</var> is null.</p></li>
+    </ol>
+   </li>
+
    <li><p>Let <var>popoverPositions</var> be an empty <span>ordered map</span>.</p></li>
 
    <li><p>Let <var>index</var> be 0.</p></li>
 
-   <li><p>Let <var>document</var> be <var>newPopover</var>'s <span>node document</span>.</p></li>
+   <li><p>Let <var>document</var> be <var>newPopoverOrTopLayerElement</var>'s <span>node
+   document</span>.</p></li>
 
    <li>
     <p>For each <var>popover</var> of <var>document</var>'s <span>showing auto popover
@@ -85343,8 +85382,8 @@ dictionary <dfn dictionary>DragEventInit</dfn> : <span>MouseEventInit</span> {
     </ol>
    </li>
 
-   <li><p><span data-x="map set">Set</span> <var>popoverPositions</var>[<var>newPopover</var>] to
-   <var>index</var>.</p></li>
+   <li><p>If <var>isPopover</var> is true, then <span data-x="map set">set</span>
+   <var>popoverPositions</var>[<var>newPopoverOrTopLayerElement</var>] to <var>index</var>.</p></li>
 
    <li><p>Increment <var>index</var> by 1.</p></li>
 
@@ -85372,12 +85411,12 @@ dictionary <dfn dictionary>DragEventInit</dfn> : <span>MouseEventInit</span> {
     </ol>
    </li>
 
-   <li><p>Run <var>checkAncestor</var> given <var>newPopover</var>'s parent node within the
-   <span>flat tree</span>.</p></li>
+   <li><p>Run <var>checkAncestor</var> given <var>newPopoverOrTopLayerElement</var>'s parent node
+   within the <span>flat tree</span>.</p></li>
 
    <li><p>Run <var>checkAncestor</var> given <var>invoker</var>.</p></li>
 
-   <li><p>return <var>topmostPopoverAncestor</var>.</p></li>
+   <li><p>Return <var>topmostPopoverAncestor</var>.</p></li>
   </ol>
 
   <p>To find the <dfn>nearest inclusive open popover</dfn> given a <code>Node</code>