Node.childNodes and Element.attributes must always return the same ob…

…ject. https://www.w3.org/Bugs/Public/show_bug.cgi?id=21271

Overview.src.html

@@ -3510,7 +3510,8 @@ <h3>Interface <code>Node</code></h3>
 <p>The <dfn title=dom-Node-childNodes><code>childNodes</code></dfn>
 attribute must return a <code>NodeList</code> rooted at the
 <span>context object</span> matching only
-<span title=concept-tree-child>children</span>.
+<span title=concept-tree-child>children</span>. The same object must be returned each
+time.
 
 <p>The <dfn title=dom-Node-firstChild><code>firstChild</code></dfn>
 attribute must return the
@@ -5829,7 +5830,8 @@ <h3>Interface <code>Element</code></h3>
 <span title=concept-element-attribute>attribute list</span>.
 The returned <span data-anolis-spec=webidl>read only array</span> must be
 live. I.e. changes to the associated
-<span title=concept-attribute>attributes</span> are reflected.
+<span title=concept-attribute>attributes</span> are reflected. The same object must be
+returned each time.
 <!-- XXXlive define live centrally somewhere for both collections and this? -->
 
 <p>The <dfn title=dom-Element-getAttribute><code>getAttribute(<var title>name</var>)</code></dfn> method must run these steps:

dom-core.html

@@ -11,7 +11,7 @@
 <p><a class="logo" href="//www.whatwg.org/"><img alt="WHATWG" height="100" src="//resources.whatwg.org/logo-dom.svg" width="100"></a></p>
 
 <h1>DOM</h1>
-<h2 class="no-num no-toc" id="living-standard-—-last-updated-9-april-2013">Living Standard — Last Updated 9 April 2013</h2>
+<h2 class="no-num no-toc" id="living-standard-—-last-updated-16-april-2013">Living Standard — Last Updated 16 April 2013</h2>
 
 <dl>
  <dt>This Version:
@@ -45,7 +45,7 @@ <h2 class="no-num no-toc" id="living-standard-—-last-updated-9-april-2013">Liv
 <p class="copyright"><a href="http://creativecommons.org/publicdomain/zero/1.0/" rel="license"><img alt="CC0" src="http://i.creativecommons.org/p/zero/1.0/80x15.png"></a>
 To the extent possible under law, the editors have waived all copyright and
 related or neighboring rights to this work. In addition, as of
-9 April 2013, the editors have made this specification available
+16 April 2013, the editors have made this specification available
 under the
 <a href="http://www.openwebfoundation.org/legal/the-owf-1-0-agreements/owfa-1-0" rel="license">Open Web Foundation Agreement Version 1.0</a>,
 which is available at
@@ -3588,7 +3588,8 @@ <h3 id="interface-node"><span class="secno">6.4 </span>Interface <code><a href="
 <p>The <dfn id="dom-node-childnodes" title="dom-Node-childNodes"><code>childNodes</code></dfn>
 attribute must return a <code><a href="#nodelist">NodeList</a></code> rooted at the
 <a href="#context-object">context object</a> matching only
-<a href="#concept-tree-child" title="concept-tree-child">children</a>.
+<a href="#concept-tree-child" title="concept-tree-child">children</a>. The same object must be returned each
+time.
 
 <p>The <dfn id="dom-node-firstchild" title="dom-Node-firstChild"><code>firstChild</code></dfn>
 attribute must return the
@@ -5894,7 +5895,8 @@ <h3 id="interface-element"><span class="secno">6.8 </span>Interface <code><a hre
 <a href="#concept-element-attribute" title="concept-element-attribute">attribute list</a>.
 The returned <a class="external" data-anolis-spec="webidl" href="http://dev.w3.org/2006/webapi/WebIDL/#dfn-read-only-array">read only array</a> must be
 live. I.e. changes to the associated
-<a href="#concept-attribute" title="concept-attribute">attributes</a> are reflected.
+<a href="#concept-attribute" title="concept-attribute">attributes</a> are reflected. The same object must be
+returned each time.
 <!-- XXXlive define live centrally somewhere for both collections and this? -->
 
 <p>The <dfn id="dom-element-getattribute" title="dom-Element-getAttribute"><code>getAttribute(<var title="">name</var>)</code></dfn> method must run these steps: