The Animation interface has a playState property which indicates whether the animation is idle, pending, playing, paused or finished.
<rdar://problem/36000982>
Created attachment 329137 [details] Patch
Comment on attachment 329137 [details] Patch Clearing flags on attachment: 329137 Committed r225807: <https://trac.webkit.org/changeset/225807>
All reviewed patches have been landed. Closing bug.