ash: Explicitly teach various components about ShelfLayoutManager.

ash/shelf/shelf.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_H_
 #define ASH_SHELF_SHELF_H_
 
 #include "ash/ash_export.h"
 #include "ash/shelf/shelf_constants.h"
 #include "ash/shelf/shelf_types.h"
@@ skipping 15 matching lines @@
 }
 
 namespace views {
 class View;
 }
 
 namespace ash {
 class FocusCycler;
 class ShelfDelegate;
 class ShelfIconObserver;
-class ShelfLayoutManager;
 class ShelfModel;
 class ShelfView;
 class ShelfWidget;
 
 namespace test {
 class ShelfTestAPI;
 }
 
 
 class ASH_EXPORT Shelf {
@@ skipping 72 matching lines @@
   ShelfDelegate* delegate_;
 
   ShelfWidget* shelf_widget_;
 
   DISALLOW_COPY_AND_ASSIGN(Shelf);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELF_SHELF_H_