dart:html perf optimization based on runing Dromaeo benchmarks

lib/dom/templates/html/impl/impl_NodeList.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.
 
 // TODO(nweiz): when all implementations we target have the same name for the
 // coreimpl implementation of List<E>, extend that rather than wrapping.
 class _ListWrapper<E> implements List<E> {
   List _list;
 
   _ListWrapper(List this._list);
@@ skipping 77 matching lines @@
   Iterator<Node> iterator() {
     // Note: NodeLists are not fixed size. And most probably length shouldn't
     // be cached in both iterator _and_ forEach method. For now caching it
     // for consistency.
     return new _FixedSizeListIterator<Node>(this);
   }
 
   // From Collection<Node>:
 
   void add(_NodeImpl value) {
-    _parent._appendChild(value);
+    _parent.$dom_appendChild(value);
   }
 
   void addLast(_NodeImpl value) {
-    _parent._appendChild(value);
+    _parent.$dom_appendChild(value);
   }
 
   void addAll(Collection<_NodeImpl> collection) {
     for (_NodeImpl node in collection) {
-      _parent._appendChild(node);      
+      _parent.$dom_appendChild(node);      
     }
   }
 
   _NodeImpl removeLast() {
     final last = this.last();
     if (last != null) {
-      _parent._removeChild(last);
+      _parent.$dom_removeChild(last);
     }
     return last;
   }
 
   void clear() {
     _parent.text = '';
   }
 
   void operator []=(int index, _NodeImpl value) {
-    _parent._replaceChild(value, this[index]);
+    _parent.$dom_replaceChild(value, this[index]);
   }
 
   void forEach(void f(Node element)) => _Collections.forEach(this, f);
 
   Collection map(f(Node element)) => _Collections.map(this, [], f);
 
   Collection<Node> filter(bool f(Node element)) =>
      new _NodeListWrapper(_Collections.filter(this, <Node>[], f));
 
   bool every(bool f(Node element)) => _Collections.every(this, f);
@@ skipping 27 matching lines @@
   void insertRange(int start, int length, [Node initialValue]) {
     throw new UnsupportedOperationException("Cannot insertRange on immutable List.");
   }
   NodeList getRange(int start, int length) =>
     new _NodeListWrapper(_Lists.getRange(this, start, length, <Node>[]));
 
   // -- end List<Node> mixins.
 
 $!MEMBERS
 }