Remove dart2js-specific annotations from childNodes

tools/dom/templates/html/impl/impl_Node.darttemplate

 // Copyright (c) 2012, 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.
 
 part of $LIBRARYNAME;
 
 /**
  * Lazy implementation of the child nodes of an element that does not request
  * the actual child nodes of an element until strictly necessary greatly
  * improving performance for the typical cases where it is not required.
@@ skipping 273 matching lines @@
    * A list of this node's children.
    *
    * ## Other resources
    *
    * * [Node.childNodes]
    * (https://developer.mozilla.org/en-US/docs/Web/API/Node.childNodes)
    * from MDN.
    */
   @DomName('Node.childNodes')
   @DocsEditable()
-  @Returns('NodeList')
-  @Creates('NodeList')
   List<Node> get childNodes {
     if (_childNodes == null) {
        List<Node> nodes = new List<Node>();
        var jsCollection = _blink.BlinkNode.instance.childNodes_Getter_(unwrap_jso(this));
        var collectionLen = jsCollection['length'];
        for (var i = 0; i < collectionLen; i++) {
          nodes.add(wrap_jso(jsCollection.callMethod('item', [i])));
        }
       _childNodes = nodes;
     }
     return _childNodes;
   }
 $else
   $if DARTIUM
   /**
    * A list of this node's children.
    *
    * ## Other resources
    *
    * * [Node.childNodes]
    * (https://developer.mozilla.org/en-US/docs/Web/API/Node.childNodes)
    * from MDN.
    */
   @DomName('Node.childNodes')
   @DocsEditable()
-  @Returns('NodeList')
-  @Creates('NodeList')
   List<Node> get childNodes => _blink.BlinkNode.instance.childNodes_Getter_(this);
   $else
   /**
    * A list of this node's children.
    *
    * ## Other resources
    *
    * * [Node.childNodes]
    * (https://developer.mozilla.org/en-US/docs/Web/API/Node.childNodes)
    * from MDN.
    */
   @DomName('Node.childNodes')
   @DocsEditable()
   @Returns('NodeList')
   @Creates('NodeList')
   final List<Node> childNodes;
 
   $endif
 $endif
 $!MEMBERS
 }