AOM: handle HDR 420/444 videos better

Also fix similar problem for VP9 (in a code path we seldom hit)

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: I86dc30003f71d5a1b32db7986f95c1c9001667a1
Reviewed-on: https://chromium-review.googlesource.com/1184246
Reviewed-by: Dale Curtis <[email protected]>
Commit-Queue: Fredrik Hubinette <[email protected]>
Cr-Commit-Position: refs/heads/master@{#585264}
2 files changed