Text tracks are not visible in fullscreen
<rdar://problem/107230116>
<rdar://107155445>
Pull request: https://github.com/WebKit/WebKit/pull/12052
Committed 262487@main (f40d4830b8c1): <https://commits.webkit.org/262487@main> Reviewed commits have been landed. Closing PR #12052 and removing active labels.