In didReceiveSample(), eraseBeginTime was being set to highestPresentationTimestamp minus a tolerance. The tolerance is not needed since highestPresentationTimestamp is loaded from exact frame timestamps, and can cause accidental frame erasure in situations where there are frames with frames smaller than the tolerance, which is the case for certain MP4 files. Test: media/media-source/media-source-append-tiny-durations.html
Created attachment 445208 [details] Patch
Committed r286485 (244824@main): <https://commits.webkit.org/244824@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 445208 [details].