When paused, some CSS animations cause CoreAnimation to pass back a null timing function when calling CACFAnimationGetTimingFunction. This patch fixes this simply by ensuring that if the output of this method is null, it does not get passed into CACFAnimationSetTimingFunction via the PlatformCAAnimation::copyTimingFunctionFrom method. This is a workaround. There is most likely a more appropriate fix in CoreAnimation to deal with the null return.
Created attachment 164482 [details] patch
Note that the CACFAnimationSetTimingFunction will always crash when null is passed in for the timingFunc parameter.
Created attachment 164485 [details] patch
<rdar://problem/12088487>
http://trac.webkit.org/changeset/128845
You seem to have killed the "Reviewed by" part of the review line :\
oops, i will fix