Add back localName and improve toString for Html nodes.

tools/dom/src/AttributeMap.dart

Index: tools/dom/src/AttributeMap.dart
diff --git a/tools/dom/src/AttributeMap.dart b/tools/dom/src/AttributeMap.dart
index 1d196e36d2d17e952176fa2cc2abadb6af0ef939..cd44ca7f67872ea597280e3988e7f11ff84d755b 100644
--- a/tools/dom/src/AttributeMap.dart
+++ b/tools/dom/src/AttributeMap.dart
@@ -44,7 +44,7 @@ abstract class _AttributeMap implements Map<String, String> {
     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;