mash: Move more shelf files to ash/common/shelf.

ash/common/shelf/wm_shelf.h

 // Copyright 2016 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_COMMON_SHELF_WM_SHELF_H_
 #define ASH_COMMON_SHELF_WM_SHELF_H_
 
 #include "ash/ash_export.h"
+#include "ash/common/shelf/shelf_layout_manager_observer.h"
 #include "ash/common/shelf/shelf_types.h"
-#include "ash/shelf/shelf_layout_manager_observer.h"
 #include "base/observer_list.h"
 
 namespace gfx {
 class Rect;
 }
 
 namespace ui {
 class GestureEvent;
 }
 
@@ skipping 113 matching lines @@
   ShelfLayoutManager* shelf_layout_manager_ = nullptr;
 
   base::ObserverList<WmShelfObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(WmShelf);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SHELF_WM_SHELF_H_