Move WKAnimationDelegate to its own header
<rdar://problem/38822299>
Created attachment 336465 [details] Patch
Created attachment 336490 [details] Patch
Comment on attachment 336490 [details] Patch Clearing flags on attachment: 336490 Committed r229960: <https://trac.webkit.org/changeset/229960>
All reviewed patches have been landed. Closing bug.