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

cc/trees/thread_proxy.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/trees/thread_proxy.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/auto_reset.h"
@@ skipping 1159 matching lines @@
     impl().layer_tree_host_impl->SetRequiresHighResToDraw();
     priority = NEW_CONTENT_TAKES_PRIORITY;
   }
 
   impl().layer_tree_host_impl->SetTreePriority(priority);
 
   // Only put the scheduler in impl latency prioritization mode if we don't
   // 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
   // after GTFO refactor of compositor-thread (http://crbug/170828).
   if (impl().layer_tree_host_impl->output_surface()) {
     impl()
         .layer_tree_host_impl->output_surface()
         ->UpdateSmoothnessTakesPriority(priority == SMOOTHNESS_TAKES_PRIORITY);
   }
 }
@@ skipping 77 matching lines @@
 
 base::WeakPtr<ProxyMain> ThreadProxy::GetMainWeakPtr() {
   return main_thread_weak_ptr_;
 }
 
 base::WeakPtr<ProxyImpl> ThreadProxy::GetImplWeakPtr() {
   return impl_thread_weak_ptr_;
 }
 
 }  // namespace cc