Cleanup: Use base/files/file_util.h instead of base/file_util.h in ash/, athena/, and chromeos/

ash/desktop_background/desktop_background_controller.cc

 // 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.
 
 #include "ash/desktop_background/desktop_background_controller.h"
 
 #include "ash/ash_switches.h"
 #include "ash/desktop_background/desktop_background_controller_observer.h"
 #include "ash/desktop_background/desktop_background_view.h"
 #include "ash/desktop_background/desktop_background_widget_controller.h"
 #include "ash/desktop_background/user_wallpaper_delegate.h"
 #include "ash/desktop_background/wallpaper_resizer.h"
 #include "ash/display/display_info.h"
 #include "ash/display/display_manager.h"
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/shell_factory.h"
 #include "ash/shell_window_ids.h"
 #include "ash/wm/root_window_layout_manager.h"
 #include "base/bind.h"
 #include "base/command_line.h"
-#include "base/file_util.h"
+#include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/synchronization/cancellation_flag.h"
 #include "base/threading/worker_pool.h"
 #include "content/public/browser/browser_thread.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/compositor/layer.h"
 #include "ui/gfx/codec/jpeg_codec.h"
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/rect.h"
@@ skipping 235 matching lines @@
                 : kShellWindowId_DesktopBackgroundContainer;
 }
 
 void DesktopBackgroundController::UpdateWallpaper() {
   current_wallpaper_.reset(NULL);
   ash::Shell::GetInstance()->user_wallpaper_delegate()->
       UpdateWallpaper(true /* clear cache */);
 }
 
 }  // namespace ash