Thanks for taking. The conversion code in GpuArcVideoService::BindDmabuf() also checks the input and does some error handling: https://codereview.chromium.org/2505733003/diff2/40001:60001/chrome/gpu/gpu_arc_video_service.cc

If using type mappings for the function is not feasible because of the error handling, please just remove the TODO in GpuArcVideoService::BindDmabuf() and close the bug.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7

commit 2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7
Author: yoshiki <yoshiki@chromium.org>
Date: Wed Dec 14 14:22:42 2016

Use mojo typemap to simplify the code using DmabufPlane

This patch introduces a typemap for video_accelerator.mojom struct and allows to use arc::ArcVideoAcceleratorDmabufPlane directly without having to convert from the arc::mojom::DmabufPlane.

BUG= 665723 
TEST=Ran YT and confirmed that histograms/Media.ArcGpuVideoDecodeAccelerator.InitializeResult is zero on chell and minnie

Review-Url: https://codereview.chromium.org/2513973002
Cr-Commit-Position: refs/heads/master@{#438512}

[modify] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/chrome/gpu/DEPS
[modify] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/chrome/gpu/arc_gpu_video_decode_accelerator.cc
[modify] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/chrome/gpu/arc_gpu_video_decode_accelerator.h
[modify] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/chrome/gpu/arc_video_accelerator.h
[modify] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/chrome/gpu/gpu_arc_video_service.cc
[modify] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/chrome/gpu/gpu_arc_video_service.h
[modify] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/components/arc/BUILD.gn
[modify] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/components/arc/common/typemaps.gni
[add] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/components/arc/common/video_accelerator.typemap
[add] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/components/arc/video_accelerator/OWNERS
[add] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/components/arc/video_accelerator/video_accelerator.h
[add] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/components/arc/video_accelerator/video_accelerator_struct_traits.cc
[add] https://crrev.com/2f600a079c2fb7e8d9b37e6c246100d5ecdd59f7/components/arc/video_accelerator/video_accelerator_struct_traits.h