Fixing cleanup of dart:html annotation generation.

tools/dom/templates/html/impl/impl_Element.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 html;
 
 // TODO(jacobr): use _Lists.dart to remove some of the duplicated
 // functionality.
 class _ChildrenElementList implements List {
   // Raw Element.
@@ skipping 478 matching lines @@
 
   void writeClasses(Set<String> s) {
     List list = new List.from(s);
     _element.$dom_className = s.join(' ');
   }
 }
 
 /**
  * An abstract class, which all HTML elements extend.
  */
-abstract class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
+$(ANNOTATIONS)abstract class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
 
   /**
    * Creates an HTML element from a valid fragment of HTML.
    *
    * The [html] fragment must represent valid HTML with a single element root,
    * which will be parsed and returned.
    *
    * Important: the contents of [html] should not contain any user-supplied
    * data. Without strict data validation it is impossible to prevent script
    * injection exploits.
@@ skipping 528 matching lines @@
 $if DART2JS
   // Optimization to improve performance until the dart2js compiler inlines this
   // method.
   static dynamic createElement_tag(String tag) =>
       JS('Element', 'document.createElement(#)', tag);
 $else
   static Element createElement_tag(String tag) =>
       document.$dom_createElement(tag);
 $endif
 }