Revert "Patched in Dartium JsInterop"

tools/dom/templates/html/impl/impl_Window.darttemplate

 // 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 $LIBRARYNAME;
 
 @DocsEditable()
 $if DART2JS
 $(ANNOTATIONS)@Native("Window,DOMWindow")
 $(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS {
@@ skipping 67 matching lines @@
    *     Location currentLocation = window.location;
    *     print(currentLocation.href); // 'http://www.example.com:80/'
    */
   Location get location => _location;
 
   // TODO: consider forcing users to do: window.location.assign('string').
   /**
    * Sets the window's location, which causes the browser to navigate to the new
    * location. [value] may be a Location object or a String.
    */
-  set location(value) {
+  void set location(value) {
     _location = value;
   }
 
   // Native getter and setter to access raw Location object.
   dynamic get _location => JS('Location|Null', '#.location', this);
-  set _location(value) {
+  void set _location(value) {
     JS('void', '#.location = #', this, value);
   }
 
   /**
    * Called to draw an animation frame and then request the window to repaint
    * after [callback] has finished (creating the animation).
    *
    * Use this method only if you need to later call [cancelAnimationFrame]. If
    * not, the preferred Dart idiom is to set animation frames by calling
    * [animationFrame], which returns a Future.
@@ skipping 208 matching lines @@
 }
 
 $if DART2JS
 class _BeforeUnloadEvent extends _WrappedEvent implements BeforeUnloadEvent {
   String _returnValue;
 
   _BeforeUnloadEvent(Event base): super(base);
 
   String get returnValue => _returnValue;
 
-  set returnValue(String value) {
+  void set returnValue(String value) {
     _returnValue = value;
     // FF and IE use the value as the return value, Chrome will return this from
     // the event callback function.
     if (JS('bool', '("returnValue" in #)', wrapped)) {
       JS('void', '#.returnValue = #', wrapped, value);
     }
   }
 }
 $endif
 
@@ skipping 26 matching lines @@
 
   ElementStream<BeforeUnloadEvent> forElement(Element e, {bool useCapture: false}) {
     return new _ElementEventStreamImpl(e, _eventType, useCapture);
   }
 
   ElementStream<BeforeUnloadEvent> _forElementList(ElementList e,
       {bool useCapture: false}) {
     return new _ElementListEventStreamImpl(e, _eventType, useCapture);
   }
 }