Handle encrypted stream in H264Decoder

- Handle the decrypt config passed to SetStream().
- The config is copied to CodecPictures and passed to the accelerator.

Bug: 820192
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: Ib3337b4bc2f972d410a07bc5af6f67a7ef2a9a2d
Reviewed-on: https://chromium-review.googlesource.com/1133974
Commit-Queue: Rintaro Kuroiwa <rkuroiwa@chromium.org>
Reviewed-by: John Rummell <jrummell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#575385}
5 files changed