Hook up ui::Compositor to Display's BeginFrameSource

cc/surfaces/onscreen_display_client.cc

 // Copyright 2014 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/surfaces/onscreen_display_client.h"
 
 #include "base/trace_event/trace_event.h"
 #include "cc/output/output_surface.h"
 #include "cc/scheduler/begin_frame_source.h"
 #include "cc/surfaces/display_scheduler.h"
@@ skipping 44 matching lines @@
   return display_->Initialize(std::move(output_surface_), scheduler_.get());
 }
 
 void OnscreenDisplayClient::CommitVSyncParameters(base::TimeTicks timebase,
                                                   base::TimeDelta interval) {
   if (interval == base::TimeDelta()) {
     // TODO(brianderson): We should not be receiving 0 intervals.
     interval = BeginFrameArgs::DefaultInterval();
   }
 
-  surface_display_output_surface_->ReceivedVSyncParameters(timebase, interval);
-  if (synthetic_frame_source_.get())
+  if (synthetic_frame_source_)
     synthetic_frame_source_->OnUpdateVSyncParameters(timebase, interval);
 }
 
 void OnscreenDisplayClient::OutputSurfaceLost() {
   output_surface_lost_ = true;
   surface_display_output_surface_->DidLoseOutputSurface();
 }
 
 void OnscreenDisplayClient::SetMemoryPolicy(const ManagedMemoryPolicy& policy) {
   surface_display_output_surface_->SetMemoryPolicy(policy);
 }
 
+BeginFrameSource* OnscreenDisplayClient::BeginFrameSourceForChildren() {
+  if (unthrottled_frame_source_)
+    return unthrottled_frame_source_.get();
+  DCHECK(synthetic_frame_source_);
+  return synthetic_frame_source_.get();
+}
+
 }  // namespace cc