Make html metadata follow the spec.

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;
 
 $if DART2JS
 $(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS native "Window,DOMWindow" {
 $else
 $(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
@@ skipping 185 matching lines @@
 
   /**
    * Gets an instance of the Indexed DB factory to being using Indexed DB.
    *
    * Use [IdbFactory.supported] to check if Indexed DB is supported on the
    * current platform.
    */
   @SupportedBrowser(SupportedBrowser.CHROME, '23.0')
   @SupportedBrowser(SupportedBrowser.FIREFOX, '15.0')
   @SupportedBrowser(SupportedBrowser.IE, '10.0')
-  @Experimental
+  @Experimental()
   IdbFactory get indexedDB =>
       JS('IdbFactory|Null',  // If not supported, returns `null`.
          '#.indexedDB || #.webkitIndexedDB || #.mozIndexedDB',
          this, this, this);
 
   @DomName('Window.console')
   Console get console => Console._safeConsole;
 
   /// Checks if _setImmediate is supported.
   static bool get _supportsSetImmediate =>
@@ skipping 21 matching lines @@
    * sandboxed file system for use. Because the file system is sandboxed,
    * applications cannot access file systems created in other web pages.
    */
   Future<FileSystem> requestFileSystem(int size, {bool persistent: false}) {
     return _requestFileSystem(persistent? 1 : 0, size);
   }
 
   @DomName('DOMWindow.convertPointFromNodeToPage')
   @SupportedBrowser(SupportedBrowser.CHROME)
   @SupportedBrowser(SupportedBrowser.SAFARI)
-  @Experimental
+  @Experimental()
   Point convertPointFromNodeToPage(Node node, Point point) {
     var result = _convertPointFromNodeToPage(node,
         new _DomPoint(point.x, point.y));
     return new Point(result.x, result.y);
   }
 
   @DomName('DOMWindow.convertPointFromPageToNode')
   @SupportedBrowser(SupportedBrowser.CHROME)
   @SupportedBrowser(SupportedBrowser.SAFARI)
-  @Experimental
+  @Experimental()
   Point convertPointFromPageToNode(Node node, Point point) {
     var result = _convertPointFromPageToNode(node,
         new _DomPoint(point.x, point.y));
     return new Point(result.x, result.y);
   }
 
   /**
    * Checks whether [convertPointFromNodeToPage] and
    * [convertPointFromPageToNode] are supported on the current platform.
    */
   static bool get supportsPointConversions => _DomPoint.supported;
 $!MEMBERS
 
   @DomName('DOMWindow.beforeunloadEvent')
-  @DocsEditable
+  @DocsEditable()
   static const EventStreamProvider<BeforeUnloadEvent> beforeUnloadEvent =
       const _BeforeUnloadEventStreamProvider('beforeunload');
 
   @DomName('DOMWindow.onbeforeunload')
-  @DocsEditable
+  @DocsEditable()
   Stream<Event> get onBeforeUnload => beforeUnloadEvent.forTarget(this);
 }
 
 /**
  * Event object that is fired before the window is closed.
  *
  * The standard window close behavior can be prevented by setting the
  * [returnValue]. This will display a dialog to the user confirming that they
  * want to close the page.
  */
@@ skipping 39 matching lines @@
       return wrapped.returnValue;
     });
 
     return controller.stream;
   }
 
   String getEventType(EventTarget target) {
     return _eventType;
   }
 }