cc: Alow animations to be aborted from either thread

cc/trees/layer_tree_host.cc

Index: cc/trees/layer_tree_host.cc
diff --git a/cc/trees/layer_tree_host.cc b/cc/trees/layer_tree_host.cc
index 6c9ee0534528bc3867dc5895c2062124224300da..118ce972eb9ec4916589e9f564095e41f4ffc5b5 100644
--- a/cc/trees/layer_tree_host.cc
+++ b/cc/trees/layer_tree_host.cc
@@ -595,6 +595,10 @@ void LayerTreeHost::SetAnimationEvents(scoped_ptr<AnimationEventsVector> events,
                                                   wall_clock_time.ToDoubleT());
           break;
 
+        case AnimationEvent::Aborted:
+          (*iter).second->NotifyAnimationAborted((*events)[event_index]);
+          break;
+
         case AnimationEvent::PropertyUpdate:
           (*iter).second->NotifyAnimationPropertyUpdate((*events)[event_index]);
           break;