Remove #pragma once from ash

ash/wm/always_on_top_controller.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_ALWAYS_ON_TOP_CONTROLLER_H_
 #define ASH_WM_ALWAYS_ON_TOP_CONTROLLER_H_
-#pragma once
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "ui/aura/window_observer.h"
 
 namespace aura {
 class Window;
 }
 
 namespace ash {
@@ skipping 27 matching lines @@
   aura::Window* default_container_;
   aura::Window* always_on_top_container_;
 
   DISALLOW_COPY_AND_ASSIGN(AlwaysOnTopController);
 };
 
 }  // namepsace internal
 }  // namepsace ash
 
 #endif  // ASH_WM_ALWAYS_ON_TOP_CONTROLLER_H_