Provide a vsync notification to the renderer

cc/layer_tree_host_impl_unittest.cc

Index: cc/layer_tree_host_impl_unittest.cc
diff --git a/cc/layer_tree_host_impl_unittest.cc b/cc/layer_tree_host_impl_unittest.cc
index c116d93538f923281ad8ec2eed651d94b809da4f..5c6ed02d291f01258c89c7b6bbed4c558fe9a266 100644
--- a/cc/layer_tree_host_impl_unittest.cc
+++ b/cc/layer_tree_host_impl_unittest.cc
@@ -91,6 +91,7 @@ public:
     virtual void didLoseOutputSurfaceOnImplThread() OVERRIDE { }
     virtual void onSwapBuffersCompleteOnImplThread() OVERRIDE { }
     virtual void onVSyncParametersChanged(base::TimeTicks, base::TimeDelta) OVERRIDE { }
+    virtual void didVSync(base::TimeTicks) OVERRIDE { }
     virtual void onCanDrawStateChanged(bool canDraw) OVERRIDE { m_onCanDrawStateChangedCalled = true; }
     virtual void onHasPendingTreeStateChanged(bool hasPendingTree) OVERRIDE { m_hasPendingTree = hasPendingTree; }
     virtual void setNeedsRedrawOnImplThread() OVERRIDE { m_didRequestRedraw = true; }