With the update, we are able to read the alpha data from Mp4parseAvifParser for avif images

Import the improvements made in mp4parse-rust repo. The changes would
save some redundant copy when calling avif related APIs and provide the
ability to get the alpha data of the parsed avif image.

Backed out for causing failures on test_case_mp4

backout: https://hg.mozilla.org/integration/autoland/rev/24d6cfe44297fcd94bfd6e87b8ebb856cc66b7c3

push: https://treeherder.mozilla.org/jobs?repo=autoland&searchStr=os%2Cx%2C10.14%2Cwebrender%2Copt%2Ctest-macosx1014-64-qr%2Fopt-gtest-1proc%2Cgtest&revision=a8c087a36965c2e235587519539621790d30b5cc&selectedTaskRun=LNU_1BJ0SraNzcYdBbD6WQ.0

failure log: https://treeherder.mozilla.org/logviewer?job_id=324286421&repo=autoland&lineNumber=29156

[task 2020-12-11T20:50:36.426Z] 20:50:36 INFO - TEST-START | MP4Metadata.test_case_mp4
[task 2020-12-11T20:50:36.426Z] 20:50:36 WARNING - TEST-UNEXPECTED-FAIL | MP4Metadata.test_case_mp4 | Expected equality of these values:
[task 2020-12-11T20:50:36.426Z] 20:50:36 INFO - tests[test].mNumberAudioTracks
[task 2020-12-11T20:50:36.427Z] 20:50:36 INFO - Which is: 2
[task 2020-12-11T20:50:36.427Z] 20:50:36 INFO - metadata.GetNumberTracks(TrackInfo::kAudioTrack).Ref()
[task 2020-12-11T20:50:36.427Z] 20:50:36 INFO - Which is: 1
[task 2020-12-11T20:50:36.427Z] 20:50:36 INFO - test_case_1185230.mp4 @ /builds/worker/checkouts/gecko/dom/media/gtest/mp4_demuxer/TestParser.cpp:280
[task 2020-12-11T20:50:36.427Z] 20:50:36 WARNING - TEST-UNEXPECTED-FAIL | MP4Metadata.test_case_mp4 | Expected equality of these values:
[task 2020-12-11T20:50:36.427Z] 20:50:36 INFO - tests[test].mNumberVideoTracks
[task 2020-12-11T20:50:36.427Z] 20:50:36 INFO - Which is: 2
[task 2020-12-11T20:50:36.427Z] 20:50:36 INFO - metadata.GetNumberTracks(TrackInfo::kVideoTrack).Ref()
[task 2020-12-11T20:50:36.427Z] 20:50:36 INFO - Which is: 1
[task 2020-12-11T20:50:36.427Z] 20:50:36 INFO - test_case_1185230.mp4 @ /builds/worker/checkouts/gecko/dom/media/gtest/mp4_demuxer/TestParser.cpp:283
[task 2020-12-11T20:50:36.428Z] 20:50:36 WARNING - TEST-UNEXPECTED-FAIL | MP4Metadata.test_case_mp4 | Expected equality of these values:
[task 2020-12-11T20:50:36.428Z] 20:50:36 INFO - tests[test].mAudioDuration
[task 2020-12-11T20:50:36.428Z] 20:50:36 INFO - Which is: 5
[task 2020-12-11T20:50:36.428Z] 20:50:36 INFO - audioInfo->mDuration.ToMicroseconds()
[task 2020-12-11T20:50:36.428Z] 20:50:36 INFO - Which is: 477460
[task 2020-12-11T20:50:36.428Z] 20:50:36 INFO - test_case_1185230.mp4 @ /builds/worker/checkouts/gecko/dom/media/gtest/mp4_demuxer/TestParser.cpp:336

Open an issue in https://github.com/mozilla/mp4parse-rust/issues/261. The fix is in https://github.com/mozilla/mp4parse-rust/pull/262. Hope we can unblock the bug 1654462 ASAP.

https://hg.mozilla.org/mozilla-central/rev/106bbc2238f0