Add DisplayScheduler for Surfaces

mojo/services/surfaces/display_impl.cc

Index: mojo/services/surfaces/display_impl.cc
diff --git a/mojo/services/surfaces/display_impl.cc b/mojo/services/surfaces/display_impl.cc
index 3fff760d2935513523b4109101ea9030e5add42d..a0f90bb63f9b95809729e90ffe35f7b4ae347fc3 100644
--- a/mojo/services/surfaces/display_impl.cc
+++ b/mojo/services/surfaces/display_impl.cc
@@ -82,15 +82,6 @@ void DisplayImpl::Draw() {
   pending_callback_.reset();
 }
 
-void DisplayImpl::DisplayDamaged() {
-}
-
-void DisplayImpl::DidSwapBuffers() {
-}
-
-void DisplayImpl::DidSwapBuffersComplete() {
-}
-
 void DisplayImpl::CommitVSyncParameters(base::TimeTicks timebase,
                                         base::TimeDelta interval) {
 }