Fixing comment constructor not functioning on IE

tools/dom/templates/html/impl/impl_Comment.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;
 
 @DocsEditable()
 $(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$MIXINS$IMPLEMENTS$NATIVESPEC {
-$!MEMBERS
-
 $if DART2JS
-  void appendRule(String rule) {
-    if (JS('bool', '("appendRule" in #)', this)) {
-      JS('', '#.appendRule(#)', this, rule);
-    } else {
-      JS('', '#.insertRule(#)', this, rule);
+  factory Comment([String data]) {
+    if (data != null) {
+      return JS('Comment', '#.createComment(#)', document, data);
     }
+    return JS('Comment', '#.createComment("")', document);
   }
 $endif
-}
+$!MEMBERS}