Breaking off part of https://bugs.webkit.org/show_bug.cgi?id=221724.
<rdar://problem/74242815>
Created attachment 420009 [details] Patch
Found 1 new test failure: http/tests/media/hls/video-duration-accessibility.html
Comment on attachment 420009 [details] Patch Looks like that test has recently become flakey: https://results.webkit.org/?suite=layout-tests&test=http%2Ftests%2Fmedia%2Fhls%2Fvideo-duration-accessibility.html
Committed r272751: <https://commits.webkit.org/r272751> All reviewed patches have been landed. Closing bug and clearing flags on attachment 420009 [details].