Add back localName and improve toString for Html nodes.

tools/dom/src/AttributeMap.dart

 // 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;
 
 abstract class _AttributeMap implements Map<String, String> {
   final Element _element;
 
   _AttributeMap(this._element);
@@ skipping 26 matching lines @@
       f(key, value);
     }
   }
 
   Collection<String> get keys {
     // TODO: generate a lazy collection instead.
     var attributes = _element.$dom_attributes;
     var keys = new List<String>();
     for (int i = 0, len = attributes.length; i < len; i++) {
       if (_matches(attributes[i])) {
-        keys.add(attributes[i].$dom_localName);
+        keys.add(attributes[i].localName);
       }
     }
     return keys;
   }
 
   Collection<String> get values {
     // TODO: generate a lazy collection instead.
     var attributes = _element.$dom_attributes;
     var values = new List<String>();
     for (int i = 0, len = attributes.length; i < len; i++) {
@@ skipping 156 matching lines @@
   int get length => keys.length;
 
   // TODO: Use lazy iterator when it is available on Map.
   bool get isEmpty => length == 0;
 
   // Helpers.
   String _attr(String key) => 'data-$key';
   bool _matches(String key) => key.startsWith('data-');
   String _strip(String key) => key.substring(5);
 }