content: Cleanup class/struct forward declarations

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_
 
 #include "base/macros.h"
 #include "gin/wrappable.h"
 
 namespace blink {
 class WebFrame;
 }
 
 namespace gin {
 class Arguments;
 }
 
 namespace v8 {
-class Function;
 class Isolate;
 class Object;
 }
 
 namespace content {
 
 // gin class for gpu benchmarking
 class GpuBenchmarking : public gin::Wrappable<GpuBenchmarking> {
  public:
   static gin::WrapperInfo kWrapperInfo;
@@ skipping 31 matching lines @@
   bool HasGpuChannel();
   bool HasGpuProcess();
   void GetGpuDriverBugWorkarounds(gin::Arguments* args);
 
   DISALLOW_COPY_AND_ASSIGN(GpuBenchmarking);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_GPU_GPU_BENCHMARKING_EXTENSION_H_