Remove GpuMemoryBufferVideoFrameData

This CL removes the deprecated GpuMemoryBufferVideoFrameData variant
of the VideoFrameData union, as well as code paths where
GpuMemoryBufferVideoFrameData is involved. As a result, the
MailboxHolder-based variant of WrapExternalGpuMemoryBuffer() is no
longer in use and therefore is also removed in this CL.

Bug: 1494911
Change-Id: I77ece1f1cdc9ecb37a04b0805fe671e09c5cc5a5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5600074


Commit-Queue: Mingjing Zhang <mjzhang@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: Vasiliy Telezhnikov <vasilyt@chromium.org>
Reviewed-by: Ken Buchanan <kenrb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1312163}