Rework Element constructors

lib/dom/frog/dom_frog.dart

Index: lib/dom/frog/dom_frog.dart
diff --git a/lib/dom/frog/dom_frog.dart b/lib/dom/frog/dom_frog.dart
index 594e5350ff17847d123cb92e9e1fd7eb0bd967a8..68c7a7da9dd94f0bd75e3fd7966010fac9ef2020 100644
--- a/lib/dom/frog/dom_frog.dart
+++ b/lib/dom/frog/dom_frog.dart
@@ -1222,6 +1222,9 @@ class _DOMStringListJs extends _DOMTypeJs implements DOMStringList native "*DOMS
   String item(int index) native;
 }
 
+class _DOMStringMapJs extends _DOMTypeJs implements DOMStringMap native "*DOMStringMap" {
+}
+
 class _DOMTokenListJs extends _DOMTypeJs implements DOMTokenList native "*DOMTokenList" {
 
   final int length;
@@ -13757,6 +13760,14 @@ interface DOMStringList extends List<String> {
 
 // WARNING: Do not edit - generated code.
 
+interface DOMStringMap {
+}
+// 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.
+
+// WARNING: Do not edit - generated code.
+
 interface DOMTokenList {
 
   final int length;