mash: Make ShelfWindowWatcher items for unknown windows.

ash/shelf/shelf_window_watcher.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_WINDOW_WATCHER_H_
 #define ASH_SHELF_SHELF_WINDOW_WATCHER_H_
 
 #include <set>
 
 #include "base/macros.h"
@@ skipping 55 matching lines @@
 
     DISALLOW_COPY_AND_ASSIGN(UserWindowObserver);
   };
 
   // Creates a ShelfItem for |window|.
   void AddShelfItem(aura::Window* window);
 
   // Removes a ShelfItem for |window|.
   void RemoveShelfItem(aura::Window* window);
 
-  // Returns the index of ShelfItem associated with |window|, or -1 if none.
-  int GetShelfItemIndexForWindow(aura::Window* window) const;
-
   // Cleans up observers on |container|.
   void OnContainerWindowDestroying(aura::Window* container);
 
   // Adds a shelf item for new windows added to the default container that have
   // a valid ShelfItemType property value.
   void OnUserWindowAdded(aura::Window* window);
 
   // Adds, updates or removes the shelf item based on a property change.
   void OnUserWindowPropertyChanged(aura::Window* window);
 
@@ skipping 22 matching lines @@
 
   // The set of windows with shelf items managed by this ShelfWindowWatcher.
   std::set<aura::Window*> user_windows_with_items_;
 
   DISALLOW_COPY_AND_ASSIGN(ShelfWindowWatcher);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELF_SHELF_WINDOW_WATCHER_H_