cc: Don't attempt main thread synchronization if it is slow.

cc/trees/thread_proxy.cc

Index: cc/trees/thread_proxy.cc
diff --git a/cc/trees/thread_proxy.cc b/cc/trees/thread_proxy.cc
index 59d8868ab4b730c7a24f235b9903fbab0678e2d4..b7deaffe18cf9de409d8caa59d10532f6a90938a 100644
--- a/cc/trees/thread_proxy.cc
+++ b/cc/trees/thread_proxy.cc
@@ -1177,9 +1177,9 @@ void ThreadProxy::RenewTreePriority() {
   // have a scroll listener. This gives the scroll listener a better chance of
   // handling scroll updates within the same frame. The tree itself is still
   // kept in prefer smoothness mode to allow checkerboarding.
-  impl().scheduler->SetImplLatencyTakesPriority(
-      priority == SMOOTHNESS_TAKES_PRIORITY &&
-      !impl().layer_tree_host_impl->scroll_affects_scroll_handler());
+  impl().scheduler->SetSmoothnessMode(
+      priority == SMOOTHNESS_TAKES_PRIORITY,
+      impl().layer_tree_host_impl->scroll_affects_scroll_handler());
 
   // Notify the the client of this compositor via the output surface.
   // TODO(epenner): Route this to compositor-thread instead of output-surface