Remove #pragma once from content

content/renderer/gpu/gpu_benchmarking_extension.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 CONTENT_RENDERER_GPU_GPU_BENCHMARKING_EXTENSION_H_
 #define CONTENT_RENDERER_GPU_GPU_BENCHMARKING_EXTENSION_H_
-#pragma once
 
 namespace v8 {
 class Extension;
 }
 
 namespace content {
 
 // V8 extension for gpu benchmarking
 class GpuBenchmarkingExtension {
  public:
   static v8::Extension* Get();
 };
 
 }  // namespace content
 
 #endif // CONTENT_RENDERER_GPU_GPU_BENCHMARKING_EXTENSION_H_