Add a setting for visibility-change-interrupts-video instead of a compile-time platform check
<rdar://problem/90248946>
Pull request: https://github.com/WebKit/WebKit/pull/4716
Committed 254892@main (3ac77f372b75): <https://commits.webkit.org/254892@main> Reviewed commits have been landed. Closing PR #4716 and removing active labels.