Add DisplayScheduler to enable BeginFrame-based scheduling of surfaces.

cc/surfaces/display.h

Index: cc/surfaces/display.h
diff --git a/cc/surfaces/display.h b/cc/surfaces/display.h
index ed96d07dd28e4a00129d31a6689a4bd7b87b51bf..db5349a423cb43fbbd625771450090905f2a9fd7 100644
--- a/cc/surfaces/display.h
+++ b/cc/surfaces/display.h
@@ -25,6 +25,7 @@ namespace cc {
 class BlockingTaskRunner;
 class DirectRenderer;
 class DisplayClient;
+class DisplayScheduler;
 class OutputSurface;
 class RendererSettings;
 class ResourceProvider;
@@ -49,7 +50,8 @@ class CC_SURFACES_EXPORT Display : public OutputSurfaceClient,
           const RendererSettings& settings);
   ~Display() override;
 
-  bool Initialize(scoped_ptr<OutputSurface> output_surface);
+  bool Initialize(scoped_ptr<OutputSurface> output_surface,
+                  DisplayScheduler* scheduler);
 
   // device_scale_factor is used to communicate to the external window system
   // what scale this was rendered at.
@@ -98,6 +100,7 @@ class CC_SURFACES_EXPORT Display : public OutputSurfaceClient,
   gfx::Size current_surface_size_;
   float device_scale_factor_;
   scoped_ptr<OutputSurface> output_surface_;
+  DisplayScheduler* scheduler_;
   scoped_ptr<ResourceProvider> resource_provider_;
   scoped_ptr<SurfaceAggregator> aggregator_;
   scoped_ptr<DirectRenderer> renderer_;