V4L2SVDA/VAAPIVDA: use visible size from decoder and pass to client

The visible size (render size) should be obtained from header parsing of
decoders. Pass visible size format to Android container to get correct
rendering size.

BUG=chromium:402760, b:37288674, b:37769238
TEST=play video on ARC++ which has different on visible and coded size
(e.g. 320x180). Check the format decoded from Chrome has correct visible
and coded size.
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2926593002
Cr-Commit-Position: refs/heads/master@{#480416}

• media/gpu/h264_decoder.cc[diff]
• media/gpu/h264_decoder.h[diff]
• media/gpu/h264_dpb.h[diff]
• media/gpu/v4l2_slice_video_decode_accelerator.cc[diff]
• media/gpu/v4l2_slice_video_decode_accelerator.h[diff]
• media/gpu/vaapi_video_decode_accelerator.cc[diff]
• media/gpu/vaapi_video_decode_accelerator.h[diff]
• media/gpu/vp8_decoder.cc[diff]
• media/gpu/vp8_picture.h[diff]
• media/gpu/vp9_decoder.cc[diff]
• media/gpu/vp9_picture.h[diff]