Remove remaining window states where window is shown with opacity 0.

ash/shelf/shelf_util.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ASH_SHELF_SHELF_UTIL_H_
 #define ASH_SHELF_SHELF_UTIL_H_
 
 #include "ash/ash_export.h"
 #include "ash/shelf/shelf_item_types.h"
 #include "ui/aura/window.h"
 
 namespace aura {
 class Window;
 }
 
 namespace ash {
 
+// A property key to store the id of the ShelfItem associated with the window.
+extern const aura::WindowProperty<ShelfID>* const kShelfID;
+
+// A property key to store the resource id and title of the item shown on the
+// shelf for this window.
 extern const aura::WindowProperty<ShelfItemDetails*>* const
     kShelfItemDetailsKey;
 
 // Associates ShelfItem of |id| with specified |window|.
 ASH_EXPORT void SetShelfIDForWindow(ShelfID id, aura::Window* window);
 
 // Returns the id of the ShelfItem associated with the specified |window|,
 // or 0 if there isn't one.
 // Note: Window of a tabbed browser will return the |ShelfID| of the
 // currently active tab.
 ASH_EXPORT ShelfID GetShelfIDForWindow(aura::Window* window);
 
 // Sets ShelfItemDetails for |window|.
 ASH_EXPORT void SetShelfItemDetailsForWindow(aura::Window* window,
                                              const ShelfItemDetails& details);
 
 // Clears ShelfItemDetails for |window|.
 // If |window| has a ShelfItem by SetShelfItemDetailsForWindow(), it will
 // be removed.
 ASH_EXPORT void ClearShelfItemDetailsForWindow(aura::Window* window);
 
 // Returns ShelfItemDetails for |window| or NULL if it doesn't have.
 // Returned ShelfItemDetails object is owned by the |window|.
 ASH_EXPORT const ShelfItemDetails* GetShelfItemDetailsForWindow(
     aura::Window* window);
 
 }  // namespace ash
 
 #endif  // ASH_SHELF_SHELF_UTIL_H_