dart:html perf optimization based on runing Dromaeo benchmarks

lib/dom/templates/html/impl/impl_NodeList.darttemplate

Index: lib/dom/templates/html/impl/impl_NodeList.darttemplate
diff --git a/lib/dom/templates/html/impl/impl_NodeList.darttemplate b/lib/dom/templates/html/impl/impl_NodeList.darttemplate
index 7b6fcf8af470999664654354dc84000535d8062c..406dd83e0fdc8d48b8b221d545ea14e713103c21 100644
--- a/lib/dom/templates/html/impl/impl_NodeList.darttemplate
+++ b/lib/dom/templates/html/impl/impl_NodeList.darttemplate
@@ -95,23 +95,23 @@ class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
   // 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;
   }
@@ -121,7 +121,7 @@ class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
   }
 
   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);