Fullscreen requires the window to be on screen. These tests must put the window on screen before attempting fullscreen.
Test failures introduced by: https://bugs.webkit.org/show_bug.cgi?id=186226
Created attachment 345133 [details] Patch
Comment on attachment 345133 [details] Patch Clearing flags on attachment: 345133 Committed r233878: <https://trac.webkit.org/changeset/233878>
All reviewed patches have been landed. Closing bug.
<rdar://problem/42267680>