[MappableSI] Convert TestVDAVideoDecoder to use MappableSI.

Allow TestVDAVideoDecoder to send a TestSharedImageInterface while
creating a VideoFrame. This in turn results in creating a VideoFrame
from a MappableSI.

Update media/gpu/chromeos/platform_video_frame_utils.h methods to take
in a SharedImageInterface* in order to allow clients to pass in a
TestSharedImageInterface* to create a MappableSI from it. If there is no
SharedImageInterface*, legacy path to create a GMB will be used until
all the clients/tests are converted to use TestSharedImageInterface.

This CL only convert TestVDAVideoDecoder. Future CLs will convert rest
of the tests using CreateGmbOrMappableSIVideoFrame() by simply passing a
TestSharedImageInterface*.

Bug: 404582006
Change-Id: I0ec6f08b143744e5071aefaae2aeb6ce6682a50f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6369531
Reviewed-by: Nathan Hebert <nhebert@chromium.org>
Commit-Queue: vikas soni <vikassoni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1453492}