Support distributing vsync info with surfaces.

cc/surfaces/display_client.h

Index: cc/surfaces/display_client.h
diff --git a/cc/surfaces/display_client.h b/cc/surfaces/display_client.h
index 6134bf5fc20430f986941a81b2d588635092b5d7..e6f54c4e5dbf98b16cf4f6bf2395cc2122601e60 100644
--- a/cc/surfaces/display_client.h
+++ b/cc/surfaces/display_client.h
@@ -6,6 +6,7 @@
 #define CC_SURFACES_DISPLAY_CLIENT_H_
 
 #include "base/memory/scoped_ptr.h"
+#include "base/time/time.h"
 
 namespace cc {
 
@@ -15,6 +16,8 @@ class DisplayClient {
  public:
   virtual scoped_ptr<OutputSurface> CreateOutputSurface() = 0;
   virtual void DisplayDamaged() = 0;
+  virtual void CommitVSyncParameters(base::TimeTicks timebase,
+                                     base::TimeDelta interval) = 0;
 
  protected:
   virtual ~DisplayClient() {}