content: Cleanup class/struct forward declarations

content/browser/gpu/gpu_process_host.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_BROWSER_GPU_GPU_PROCESS_HOST_H_
 #define CONTENT_BROWSER_GPU_GPU_PROCESS_HOST_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 33 matching lines @@
 struct GpuPreferences;
 struct SyncToken;
 }
 
 namespace service_manager {
 class InterfaceProvider;
 }
 
 namespace content {
 class BrowserChildProcessHostImpl;
-class GpuMainThread;
 class InProcessChildThreadParams;
 class ShaderDiskCache;
 
 typedef base::Thread* (*GpuMainThreadFactoryFunction)(
     const InProcessChildThreadParams&, const gpu::GpuPreferences&);
 
 class GpuProcessHost : public BrowserChildProcessHostDelegate,
                        public IPC::Sender,
                        public base::NonThreadSafe {
  public:
@@ skipping 223 matching lines @@
   ClientIdToShaderCacheMap client_id_to_shader_cache_;
 
   std::string shader_prefix_key_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuProcessHost);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_GPU_GPU_PROCESS_HOST_H_