cc: Introduce BeginFrame sequence numbers and acknowledgements.

services/ui/surfaces/gpu_compositor_frame_sink.cc

Index: services/ui/surfaces/gpu_compositor_frame_sink.cc
diff --git a/services/ui/surfaces/gpu_compositor_frame_sink.cc b/services/ui/surfaces/gpu_compositor_frame_sink.cc
index 22f127935e215bcbffef2482c5e9118c118e89c7..e8f3682b7be0b829853b1feb02eeb84656b97a75 100644
--- a/services/ui/surfaces/gpu_compositor_frame_sink.cc
+++ b/services/ui/surfaces/gpu_compositor_frame_sink.cc
@@ -47,6 +47,11 @@ void GpuCompositorFrameSink::SubmitCompositorFrame(
   support_.SubmitCompositorFrame(local_frame_id, std::move(frame));
 }
 
+void GpuCompositorFrameSink::BeginFrameDidNotDraw(
+    const cc::BeginFrameAck& ack) {
+  support_.BeginFrameDidNotDraw(ack);
+}
+
 void GpuCompositorFrameSink::DidReceiveCompositorFrameAck() {
   client_->DidReceiveCompositorFrameAck();
 }