The HTMLVideoElement, HTMLAudioElement, and HTMLTrackElement constructors check both document.settings().mediaEnabled() and MediaPlayer::isAvailable to see if media is disabled. Ports should disable the setting if they don't want media elements, so the later is redundant.
<rdar://problem/38802687>
Created attachment 336403 [details] Patch
Comment on attachment 336403 [details] Patch Clearing flags on attachment: 336403 Committed r229915: <https://trac.webkit.org/changeset/229915>
All reviewed patches have been landed. Closing bug.