Ensure that newly-constructed elements don't have parents.

client/html/src/ElementWrappingImplementation.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // TODO(jacobr): use Lists.dart to remove some of the duplicated functionality.
 class _ChildrenElementList implements ElementList {
   // Raw Element.
   final _element;
   final _childElements;
 
@@ skipping 522 matching lines @@
     if (match !== null) {
       tag = match.group(1).toLowerCase();
       if (_CUSTOM_PARENT_TAG_MAP.containsKey(tag)) {
         parentTag = _CUSTOM_PARENT_TAG_MAP[tag];
       }
     }
     // TODO(jacobr): make type dom.HTMLElement when dartium allows it.
     var temp = dom.document.createElement(parentTag);
     temp.innerHTML = html;
 
+    var element;

[Jacob, 2012/02/14 02:31:06]

var ==> Element

     if (temp.childElementCount == 1) {
-      return LevelDom.wrapElement(temp.firstElementChild);     
+      element = LevelDom.wrapElement(temp.firstElementChild);
     } else if (parentTag == 'html' && temp.childElementCount == 2) {
       // Work around for edge case in WebKit and possibly other browsers where
       // both body and head elements are created even though the inner html
       // only contains a head or body element.
-      return LevelDom.wrapElement(temp.children.item(tag == 'head' ? 0 : 1));
+      element = LevelDom.wrapElement(temp.children.item(tag == 'head' ? 0 : 1));
     } else {
       throw new IllegalArgumentException('HTML had ${temp.childElementCount} ' +
           'top level elements but 1 expected');
     }
+    element.remove();
+    return element;
   }
 
   /** @domName Document.createElement */
   factory ElementWrappingImplementation.tag(String tag) {
     return LevelDom.wrapElement(dom.document.createElement(tag));
   }
 
   ElementWrappingImplementation._wrap(ptr) : super._wrap(ptr);
 
   ElementAttributeMap _elementAttributeMap;
@@ skipping 215 matching lines @@
 
   ElementEvents get on() {
     if (_on === null) {
       _on = new ElementEventsImplementation._wrap(_ptr);
     }
     return _on;
   }
 
   Element clone(bool deep) => super.clone(deep);
 }