In WK1 WebVideoFullscreen interface may be accessed from WK1 main thread instead of UI thread.
Created attachment 271362 [details] Patch
rdar://problem/22460539
Comment on attachment 271362 [details] Patch Clearing flags on attachment: 271362 Committed r199193: <http://trac.webkit.org/changeset/199193>
All reviewed patches have been landed. Closing bug.