Run draw callback immediately if no Display is damaged.

content/browser/compositor/delegated_frame_host.cc

Index: content/browser/compositor/delegated_frame_host.cc
diff --git a/content/browser/compositor/delegated_frame_host.cc b/content/browser/compositor/delegated_frame_host.cc
index cbf43b5237810e353f556bbbc6bea2dc1aeaef69..b329e4dea20dd38b49495ac324ef64fa277ea742 100644
--- a/content/browser/compositor/delegated_frame_host.cc
+++ b/content/browser/compositor/delegated_frame_host.cc
@@ -372,6 +372,8 @@ void DelegatedFrameHost::SwapDelegatedFrame(
     last_output_surface_id_ = output_surface_id;
   }
   bool immediate_ack = !compositor_;
+  pending_delegated_ack_count_++;
+
   if (frame_size.IsEmpty()) {
     DCHECK(frame_data->resource_list.empty());
     EvictDelegatedFrame();
@@ -450,8 +452,6 @@ void DelegatedFrameHost::SwapDelegatedFrame(
   if (!damage_rect_in_dip.IsEmpty())
     client_->GetLayer()->OnDelegatedFrameDamage(damage_rect_in_dip);
 
-  pending_delegated_ack_count_++;
-
   if (immediate_ack) {
     SendDelegatedFrameAck(output_surface_id);
   } else if (!use_surfaces_) {
@@ -492,7 +492,8 @@ void DelegatedFrameHost::SendDelegatedFrameAck(uint32 output_surface_id) {
   pending_delegated_ack_count_--;
 }
 
-void DelegatedFrameHost::SurfaceDrawn(uint32 output_surface_id, bool drawn) {
+void DelegatedFrameHost::SurfaceDrawn(uint32 output_surface_id,
+                                      cc::SurfaceDrawStatus drawn) {
   SendDelegatedFrameAck(output_surface_id);
 }