Convert //ash from scoped_ptr to std::unique_ptr

ash/wm/system_modal_container_layout_manager.h

 // Copyright (c) 2012 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_WM_SYSTEM_MODAL_CONTAINER_LAYOUT_MANAGER_H_
 #define ASH_WM_SYSTEM_MODAL_CONTAINER_LAYOUT_MANAGER_H_
 
 #include <vector>
 
 #include "ash/ash_export.h"
 #include "ash/snap_to_pixel_layout_manager.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
 #include "ui/aura/window_observer.h"
 #include "ui/keyboard/keyboard_controller_observer.h"
 
 namespace aura {
 class Window;
 class EventFilter;
 }
 namespace gfx {
 class Rect;
 }
@@ skipping 77 matching lines @@
 
   // A stack of modal windows. Only the topmost can receive events.
   std::vector<aura::Window*> modal_windows_;
 
   DISALLOW_COPY_AND_ASSIGN(SystemModalContainerLayoutManager);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_SYSTEM_MODAL_CONTAINER_LAYOUT_MANAGER_H_