Make ChildProcessHost be used through an interface in content/public, instead of by inheritence.

content/browser/gpu/gpu_process_host.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_GPU_GPU_PROCESS_HOST_H_
 #define CONTENT_BROWSER_GPU_GPU_PROCESS_HOST_H_
 #pragma once
 
 #include <map>
 #include <queue>
@@ skipping 84 matching lines @@
   virtual void OnProcessLaunched() OVERRIDE;
   virtual void OnProcessCrashed(int exit_code) OVERRIDE;
 
   // Message handlers.
   void OnChannelEstablished(const IPC::ChannelHandle& channel_handle);
   void OnCommandBufferCreated(const int32 route_id);
   void OnDestroyCommandBuffer(
       gfx::PluginWindowHandle window, int32 renderer_id, int32 render_view_id);
   void OnGraphicsInfoCollected(const content::GPUInfo& gpu_info);
 
-  bool LaunchGpuProcess();
+  bool LaunchGpuProcess(const std::string& channel_id);
 
   void SendOutstandingReplies();
   void EstablishChannelError(
       EstablishChannelCallback* callback,
       const IPC::ChannelHandle& channel_handle,
       base::ProcessHandle renderer_process_for_gpu,
       const content::GPUInfo& gpu_info);
   void CreateCommandBufferError(CreateCommandBufferCallback* callback,
                                 int32 route_id);
 
@@ skipping 40 matching lines @@
 
   // Master switch for enabling/disabling GPU acceleration for the current
   // browser session. It does not change the acceleration settings for
   // existing tabs, just the future ones.
   CONTENT_EXPORT static bool gpu_enabled_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuProcessHost);
 };
 
 #endif  // CONTENT_BROWSER_GPU_GPU_PROCESS_HOST_H_