[cc] Fix CompositorFrameSinkSupport BeginFrameAck interface.

services/ui/ws/window_tree_client_unittest.cc

Index: services/ui/ws/window_tree_client_unittest.cc
diff --git a/services/ui/ws/window_tree_client_unittest.cc b/services/ui/ws/window_tree_client_unittest.cc
index edb216a1d20959de6ad5d7c522a7ca3134c5f490..7b91b258554011a42c4309542cf580ba8f73b8ca 100644
--- a/services/ui/ws/window_tree_client_unittest.cc
+++ b/services/ui/ws/window_tree_client_unittest.cc
@@ -2185,6 +2185,8 @@ TEST_F(WindowTreeClientTest, SurfaceIdPropagation) {
   render_pass->SetNew(1, frame_rect, frame_rect, gfx::Transform());
   compositor_frame.render_pass_list.push_back(std::move(render_pass));
   compositor_frame.metadata.device_scale_factor = 1.f;
+  compositor_frame.metadata.begin_frame_ack =
+      cc::BeginFrameAck(0, 1, 1, 0, true);
   cc::LocalSurfaceId local_surface_id(1, base::UnguessableToken::Create());
   surface_ptr->SubmitCompositorFrame(local_surface_id,
                                      std::move(compositor_frame));