gpu_arc_vd: Introduce new VD-based ARC video decoder.

The GpuArcVideoDecodeAccelerator bridges between ARC++/ARCVM and the
Chrome video decode accelerator. The GpuArcVideoDecodeAccelerator
implements the VideoDecodeAccelerator interface which has been
deprecated in favor of the VideoDecoder interface. To allow interaction
with VideoDecoder-based decoders a wrapper is used translating between
the VDA and VD interfaces.

This CL introduces a new GpuArcVideoDecoder that can natively
communicate with the VideoDecoder interface. Currently the
GpuArcVideoDecoder implements the mojo::VideoDecodeAccelerator
interface, but in a future step a new mojo::VideoDecoder interface
will be introduced.

TEST=arc.VideoDecodeAccel.h264_vm

BUG=189278506

Change-Id: Iba7b12656878612219628354466eee5ea92e5dd4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3026365
Commit-Queue: David Staessens <dstaessens@chromium.org>
Reviewed-by: Chih-Yu Huang <akahuang@chromium.org>
Cr-Commit-Position: refs/heads/main@{#915870}