Remove #pragma once from content

content/browser/renderer_host/backing_store_gtk.h

 // Copyright (c) 2011 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 CONTENT_BROWSER_RENDERER_HOST_BACKING_STORE_GTK_H_
 #define CONTENT_BROWSER_RENDERER_HOST_BACKING_STORE_GTK_H_
-#pragma once
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "build/build_config.h"
 #include "content/browser/renderer_host/backing_store.h"
 #include "content/common/content_export.h"
 #include "ui/base/x/x11_util.h"
 
@@ skipping 81 matching lines @@
   XID pixmap_;
   // This is the RENDER picture pointing at |pixmap_|.
   XID picture_;
   // This is a default graphic context, used in XCopyArea
   void* pixmap_gc_;
 
   DISALLOW_COPY_AND_ASSIGN(BackingStoreGtk);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_BACKING_STORE_GTK_H_