Use ParamTraits for media::BitstreamBuffer.

content/common/gpu/client/gpu_video_decode_accelerator_host.cc

Index: content/common/gpu/client/gpu_video_decode_accelerator_host.cc
diff --git a/content/common/gpu/client/gpu_video_decode_accelerator_host.cc b/content/common/gpu/client/gpu_video_decode_accelerator_host.cc
index 19a336b9ca30af573159449f4eef9911b2b01b8d..15b514a2b5e7ace52f2aa26da758111845488541 100644
--- a/content/common/gpu/client/gpu_video_decode_accelerator_host.cc
+++ b/content/common/gpu/client/gpu_video_decode_accelerator_host.cc
@@ -119,24 +119,16 @@ void GpuVideoDecodeAcceleratorHost::Decode(
   DCHECK(CalledOnValidThread());
   if (!channel_)
     return;
-
-  base::SharedMemoryHandle handle = channel_->ShareToGpuProcess(
-      bitstream_buffer.handle());
+  media::BitstreamBuffer buffer_to_send = bitstream_buffer;
+  base::SharedMemoryHandle handle =

[dcheng, 2016/02/18 21:06:09]

I think the IPC subsystem has been improved so you don't need to explicitly dupe
anymore, but erikchen@ should confirm.

[erikchen, 2016/02/18 21:07:31]

correct. no need to dupe shared memory handles before passing them to ipc.

[Owen Lin, 2016/02/23 03:40:11]

Thanks. That's great. But I think we should do that in anther CL where I am
going to remove the function GpuChannelHost::ShareToGpuProcess(), since it is
not needed.

+      channel_->ShareToGpuProcess(bitstream_buffer.handle());
   if (!base::SharedMemory::IsHandleValid(handle)) {
     NOTREACHED() << "Failed to duplicate buffer handler";
     return;
   }
-
-  AcceleratedVideoDecoderMsg_Decode_Params params;
-  params.bitstream_buffer_id = bitstream_buffer.id();
-  params.buffer_handle = handle;
-  params.size = bitstream_buffer.size();
-  params.presentation_timestamp = bitstream_buffer.presentation_timestamp();
-  params.key_id = bitstream_buffer.key_id();
-  params.iv = bitstream_buffer.iv();
-  params.subsamples = bitstream_buffer.subsamples();
-
-  Send(new AcceleratedVideoDecoderMsg_Decode(decoder_route_id_, params));
+  buffer_to_send.set_handle(handle);
+  Send(
+      new AcceleratedVideoDecoderMsg_Decode(decoder_route_id_, buffer_to_send));
 }
 
 void GpuVideoDecodeAcceleratorHost::AssignPictureBuffers(