Remove hierarchy restrictions and introduce top layer add/remove. Fixes

#6 (comment)

Overview.html

@@ -9,7 +9,7 @@
 
 <hgroup>
  <h1 class="p-name">Fullscreen API</h1>
- <h2 class="no-num no-toc">Living Standard — Last Updated 13 July 2015</h2>
+ <h2 class="no-num no-toc">Living Standard — Last Updated 15 July 2015</h2>
 </hgroup>
 
  <dl>
@@ -130,12 +130,14 @@ <h2 id="model"><span class="secno">3 </span>Model</h2>
 whose <a href="#fullscreen-flag">fullscreen flag</a> is set, if any, and null otherwise.
 
 <p>To <dfn id="fullscreen-an-element">fullscreen an <var>element</var></dfn> within a <var title="">document</var>, set
-the <var title="">element</var>'s <a href="#fullscreen-flag">fullscreen flag</a>, and add, or move if already
-present, it on top of <var title="">document</var>'s <a href="#top-layer">top layer</a>.
+the <var title="">element</var>'s <a href="#fullscreen-flag">fullscreen flag</a> and
+<a href="#concept-top-layer-add" title="concept-top-layer-add">add</a> it to <var title="">document</var>'s
+<a href="#top-layer">top layer</a>.
 
 <p>To <dfn id="unfullscreen-an-element">unfullscreen an <var>element</var></dfn> within a <var title="">document</var>,
-unset the <var title="">element</var>'s <a href="#fullscreen-flag">fullscreen flag</a>, and remove it from
-<var title="">document</var>'s <a href="#top-layer">top layer</a>.
+unset the <var title="">element</var>'s <a href="#fullscreen-flag">fullscreen flag</a> and
+<a href="#concept-top-layer-remove" title="concept-top-layer-remove">remove</a> it from <var title="">document</var>'s
+<a href="#top-layer">top layer</a>.
 
 <p>To <dfn id="unfullscreen-a-document">unfullscreen a <var>document</var></dfn>,
 <a href="#unfullscreen-an-element" title="unfullscreen an element">unfullscreen</a> all
@@ -248,13 +250,6 @@ <h2 id="api"><span class="secno">4 </span>API</h2>
  <a href="#fullscreen-enabled-flag">fullscreen enabled flag</a> is set.
  <!-- The fullscreen enabled flag is propagated properly by HTML -->
 
- <li><p><var title="">element</var>'s
- <a class="external" data-anolis-spec="dom" href="https://dom.spec.whatwg.org/#concept-node-document" title="concept-node-document">node document</a>'s
- <a href="#fullscreen-element">fullscreen element</a> is null, or is an
- <a class="external" data-anolis-spec="dom" href="https://dom.spec.whatwg.org/#concept-tree-inclusive-ancestor" title="concept-tree-inclusive-ancestor">inclusive ancestor</a>
- of <var title="">element</var>.
- <!-- If /element/ is the fullscreen element, nothing happens -->
-
  <li><p><var title="">element</var> has no
  <a class="external" data-anolis-spec="dom" href="https://dom.spec.whatwg.org/#concept-tree-ancestor" title="concept-tree-ancestor">ancestor</a>
  <a class="external" data-anolis-spec="dom" href="https://dom.spec.whatwg.org/#concept-element" title="concept-element">element</a> whose
@@ -580,6 +575,13 @@ <h3 id="new-stacking-layer"><span class="secno">6.1 </span>New stacking layer</h
  <code title="">top</code> is zero.
 </ul>
 
+<p>To <dfn id="concept-top-layer-add" title="concept-top-layer-add">add</dfn> an <var>element</var> to a
+<var title="">top layer</var>, add, or move if already present, <var>element</var> on top of
+<var title="">top layer</var>.
+
+<p>To <dfn id="concept-top-layer-remove" title="concept-top-layer-remove">remove</dfn> an <var>element</var> from a
+<var title="">top layer</var>, remove <var>element</var> from <var title="">top layer</var>.
+
 
 <h3 id="::backdrop-pseudo-element"><span class="secno">6.2 </span><code title="">::backdrop</code> pseudo-element</h3>
 

Overview.src.html

@@ -115,12 +115,14 @@ <h2>Model</h2>
 whose <span>fullscreen flag</span> is set, if any, and null otherwise.
 
 <p>To <dfn>fullscreen an <var>element</var></dfn> within a <var title>document</var>, set
-the <var title>element</var>'s <span>fullscreen flag</span>, and add, or move if already
-present, it on top of <var title>document</var>'s <span>top layer</span>.
+the <var title>element</var>'s <span>fullscreen flag</span> and
+<span title=concept-top-layer-add>add</span> it to <var title>document</var>'s
+<span>top layer</span>.
 
 <p>To <dfn>unfullscreen an <var>element</var></dfn> within a <var title>document</var>,
-unset the <var title>element</var>'s <span>fullscreen flag</span>, and remove it from
-<var title>document</var>'s <span>top layer</span>.
+unset the <var title>element</var>'s <span>fullscreen flag</span> and
+<span title=concept-top-layer-remove>remove</span> it from <var title>document</var>'s
+<span>top layer</span>.
 
 <p>To <dfn>unfullscreen a <var>document</var></dfn>,
 <span title="unfullscreen an element">unfullscreen</span> all
@@ -233,13 +235,6 @@ <h2>API</h2>
  <span>fullscreen enabled flag</span> is set.
  <!-- The fullscreen enabled flag is propagated properly by HTML -->
 
- <li><p><var title>element</var>'s
- <span data-anolis-spec=dom title=concept-node-document>node document</span>'s
- <span>fullscreen element</span> is null, or is an
- <span data-anolis-spec=dom title=concept-tree-inclusive-ancestor>inclusive ancestor</span>
- of <var title>element</var>.
- <!-- If /element/ is the fullscreen element, nothing happens -->
-
  <li><p><var title>element</var> has no
  <span data-anolis-spec=dom title=concept-tree-ancestor>ancestor</span>
  <span data-anolis-spec=dom title=concept-element>element</span> whose
@@ -565,6 +560,13 @@ <h3>New stacking layer</h3>
  <code title>top</code> is zero.
 </ul>
 
+<p>To <dfn title=concept-top-layer-add>add</dfn> an <var>element</var> to a
+<var title>top layer</var>, add, or move if already present, <var>element</var> on top of
+<var title>top layer</var>.
+
+<p>To <dfn title=concept-top-layer-remove>remove</dfn> an <var>element</var> from a
+<var title>top layer</var>, remove <var>element</var> from <var title>top layer</var>.
+
 
 <h3><code title>::backdrop</code> pseudo-element</h3>