Added GPU process "echo" IPC message.

content/common/gpu/gpu_channel.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_COMMON_GPU_GPU_CHANNEL_H_
 #define CONTENT_COMMON_GPU_GPU_CHANNEL_H_
 #pragma once
 
 #include <queue>
 #include <set>
@@ skipping 132 matching lines @@
       const GPUCreateCommandBufferConfig& init_params,
       IPC::Message* reply_message);
   void OnDestroyCommandBuffer(int32 route_id, IPC::Message* reply_message);
 
   void OnCreateOffscreenSurface(const gfx::Size& size,
                                 IPC::Message* reply_message);
   void OnDestroySurface(int route_id);
 
   void OnCreateTransportTexture(int32 context_route_id, int32 host_id);
 
+  void OnEcho(const IPC::Message& message);
+
   // The lifetime of objects of this class is managed by a GpuChannelManager.
   // The GpuChannelManager destroy all the GpuChannels that they own when they
   // are destroyed. So a raw pointer is safe.
   GpuChannelManager* gpu_channel_manager_;
 
   scoped_ptr<IPC::SyncChannel> channel_;
 
   std::queue<IPC::Message*> deferred_messages_;
 
   // The id of the renderer who is on the other side of the channel.
@@ skipping 28 matching lines @@
   gpu::gles2::DisallowedExtensions disallowed_extensions_;
   GpuWatchdog* watchdog_;
   bool software_;
 
   ScopedRunnableMethodFactory<GpuChannel> task_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuChannel);
 };
 
 #endif  // CONTENT_COMMON_GPU_GPU_CHANNEL_H_