Implement GpuArcVideoService for arc video accelerator

content/common/gpu/gpu_messages.h

Index: content/common/gpu/gpu_messages.h
diff --git a/content/common/gpu/gpu_messages.h b/content/common/gpu/gpu_messages.h
index 961c33fd6d5bf15fa34af03353693236731ac7b4..b6f0fd50d4c78ceac1ab4f17fe2e259cea0548bb 100644
--- a/content/common/gpu/gpu_messages.h
+++ b/content/common/gpu/gpu_messages.h
@@ -847,3 +847,26 @@ IPC_MESSAGE_ROUTED0(AcceleratedJpegDecoderMsg_Destroy)
 IPC_MESSAGE_ROUTED2(AcceleratedJpegDecoderHostMsg_DecodeAck,
                     int32_t, /* bitstream_buffer_id */
                     media::JpegDecodeAccelerator::Error /* error */)
+
+#if defined(OS_CHROMEOS)
+//------------------------------------------------------------------------------
+// Arc Video Accelerator Messages
+// These messages are sent from the Browser process to GPU process.
+
+// Tells the GPU process to create a new channel for communication with
+// ArcVideoAccelerator. The channel is returned using
+// GpuHostMsg_ArcVideoAcceleratorChannelCreated message.
+IPC_MESSAGE_CONTROL0(GpuMsg_CreateArcVideoAcceleratorChannel)
+
+// Tells the GPU process to shutdown arc video service and terminate all
+// instances of ArcVideoAccelerator.
+IPC_MESSAGE_CONTROL0(GpuMsg_ShutdownArcVideoService)
+
+//------------------------------------------------------------------------------
+// Arc Video Accelerator Host Messages
+// These messages are sent from the GPU process to Browser process.
+
+// Response from GPU to a GpuMsg_CreateArcVideoAcceleratorChannel message.
+IPC_MESSAGE_CONTROL1(GpuHostMsg_ArcVideoAcceleratorChannelCreated,
+                     IPC::ChannelHandle /* handle to channel */)
+#endif