media/gpu/VEA unittest: Enable VEAs to test with any yuv format stream

VEA unittest is only able to test I420 format input file.
This enables it to test any yuv format stream.

NV12, NV12 and YV21 formated raw videos are created by following commands.
$ ffmpeg -s 320x192 -i bear_320x192_40frames.yuv -pix_fmt nv12 bear_320x192_40frames.nv12.yuv
$ ffmpeg -s 320x192 -i bear_320x192_40frames.yuv -pix_fmt nv21 bear_320x192_40frames.nv21.yuv
$ ffmpeg -s 320x192 -i bear_320x192_40frames.yuv -pix_fmt yuv420p -vf shuffleplanes=0:2:1 bear_320x192_40frames.yv12.yuv

BUG=chromium:894381
TEST=[kevin] ./video_encode_accelerator_unittest --test_stream_data=bear_320x192_40frames.nv12.yuv:320:192:1:bear.out:200000:30:::6 --ozone-platform=gbm

Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: I8a6b142671fc0532ba872f7eff966d43a2848ad9
Reviewed-on: https://chromium-review.googlesource.com/c/1135106
Commit-Queue: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Kuang-che Wu <kcwu@chromium.org>
Reviewed-by: Alexandre Courbot <acourbot@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599158}

media/test/data/README.md

@@ -574,6 +574,18 @@ The frame sizes change between 1080p and 720p every 24 frames.
 First 40 raw i420 frames of bear-1280x720.mp4 scaled down to 320x192 for
 video_encode_accelerator_unittest.
 
+#### bear_320x192_40frames.nv12.yuv
+First 40 raw nv12 frames of bear-1280x720.mp4 scaled down to 320x192 for
+video_encode_accelerator_unittest.
+
+#### bear_320x192_40frames.nv21.yuv
+First 40 raw nv21 frames of bear-1280x720.mp4 scaled down to 320x192 for
+video_encode_accelerator_unittest.
+
+#### bear_320x192_40frames.yv12.yuv
+First 40 raw yv12 frames of bear-1280x720.mp4 scaled down to 320x192 for
+video_encode_accelerator_unittest.
+
 ###  VP9 parser test files:
 
 #### bear-vp9.ivf