Revert revision 11570, this still has dartium failures.

lib/dom/dart2js/dom_dart2js.dart

Index: lib/dom/dart2js/dom_dart2js.dart
===================================================================
--- lib/dom/dart2js/dom_dart2js.dart	(revision 11575)
+++ lib/dom/dart2js/dom_dart2js.dart	(working copy)
@@ -12064,14 +12064,6 @@
 // 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.
 
-class _DOMFormDataFactoryProvider {
-  factory DOMFormData([FormElement form]) native
-      '''return new DOMFormData(form);''';
-}
-// 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.
-
 class _DOMParserFactoryProvider {
   factory DOMParser() native
       '''return new DOMParser();''';
@@ -13631,10 +13623,8 @@
 
 // WARNING: Do not edit - generated code.
 
-interface FormData default _FormDataFactoryProvider {
+interface FormData {
 
-  FormData([FormElement form]);
-
   void append(String name, String value, String filename);
 }
 
@@ -25221,15 +25211,6 @@
 ''';
 }
 
-class _FormDataFactoryProvider {
-
-  factory FormData([FormElement form = null]) native '''
-    if (form == null) return new FormData();
-    return new FormData(form);
-  ''';
-
-}
-
 class _WebKitPointFactoryProvider {
 
   factory WebKitPoint(num x, num y) native '''return new WebKitPoint(x, y);''';