Bug 1425837 - Part 7: Drop the hard-code disabling compositor animations on individual transforms. r=hiro,birtles

Drop the hack which prevents individual transform running on the
compositor thread.

Depends on D22566

Differential Revision: https://phabricator.services.mozilla.com/D22567

--HG--
extra : moz-landing-system : lando

dom/animation/KeyframeEffect.cpp

@@ -1498,13 +1498,6 @@ bool KeyframeEffect::ShouldBlockAsyncTransformAnimations(
     }
   }
 
-  // FIXME: Bug 1425837: drop this hack.
-  // XXX cku temporarily disable async-animation when this frame has any
-  // individual transforms before bug 1425837 been fixed.
-  if (aFrame->StyleDisplay()->HasIndividualTransform()) {
-    return true;
-  }
-
   return false;
 }