Revert "- Update _blink library using dart:js instead of native keyword"

tools/dom/src/native_DOMImplementation.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;
 
 class _Property {
   _Property(this.name) :
       _hasValue = false,
       writable = false,
@@ skipping 169 matching lines @@
   }
 
   static Element getAndValidateNativeType(Type type, String tagName) {
     var element = new Element.tag(tagName);
     if (!isTypeSubclassOf(type, element.runtimeType)) {
       return null;
     }
     return element;
   }
 
-  static window() => wrap_jso(_blink.Blink_Utils.window()['window']);
-  // TODO(terry): Above enabled for Dartium w/ interop and remove below static window() for C++.
-  // static window() => _blink.Blink_Utils.window();
+  // TODO(terry): Enable below for Dartium w/ interop and remove other static window().
+  // static window() => wrap_jso(_blink.Blink_Utils.window()['window']);
+  static window() => _blink.Blink_Utils.window();
 
   static forwardingPrint(String message) => _blink.Blink_Utils.forwardingPrint(message);
   static void spawnDomHelper(Function f, int replyTo) =>
       _blink.Blink_Utils.spawnDomHelper(f, replyTo);
 
   // TODO(vsm): Make this API compatible with spawnUri.  It should also
   // return a Future<Isolate>.
   static spawnDomUri(String uri) => _blink.Blink_Utils.spawnDomUri(uri);
 
   // The following methods were added for debugger integration to make working
@@ skipping 906 matching lines @@
   throw new UnimplementedError("scheduleMicrotask in background isolates "
                                "are not supported in the browser"));
 
 void _initializeCustomElement(Element e) {
   _Utils.initializeCustomElement(e);
 }
 
 // Class for unsupported native browser 'DOM' objects.
 class _UnsupportedBrowserObject extends NativeFieldWrapperClass2 {
 }