Implement temporary reference assignment with DisplayCompositor.

services/ui/ws/server_window_compositor_frame_sink_manager.cc

Index: services/ui/ws/server_window_compositor_frame_sink_manager.cc
diff --git a/services/ui/ws/server_window_compositor_frame_sink_manager.cc b/services/ui/ws/server_window_compositor_frame_sink_manager.cc
index 1053fafad1f4b3ddf5d4d6d49694f7e7b98b6726..dc4404c9af7e440c6a2afcffad718772dab783f2 100644
--- a/services/ui/ws/server_window_compositor_frame_sink_manager.cc
+++ b/services/ui/ws/server_window_compositor_frame_sink_manager.cc
@@ -29,25 +29,17 @@ void ServerWindowCompositorFrameSinkManager::CreateRootCompositorFrameSink(
   cc::FrameSinkId frame_sink_id(WindowIdToTransportId(window_->id()), 0);
 
   if (!frame_sink_data_)
-    frame_sink_data_ = base::MakeUnique<CompositorFrameSinkData>();
+    CreateCompositorFrameSinkData();
 
   frame_sink_data_->frame_sink_id = frame_sink_id;
-  cc::mojom::MojoCompositorFrameSinkPrivateRequest private_request;
-  if (frame_sink_data_->pending_compositor_frame_sink_request.is_pending()) {
-    private_request =
-        std::move(frame_sink_data_->pending_compositor_frame_sink_request);
-  } else {
-    private_request =
-        mojo::MakeRequest(&frame_sink_data_->compositor_frame_sink);
-  }
 
   // TODO(fsamuel): AcceleratedWidget cannot be transported over IPC for Mac
   // or Android. We should instead use GpuSurfaceTracker here on those
   // platforms.
   window_->delegate()->GetDisplayCompositor()->CreateRootCompositorFrameSink(
       frame_sink_id, widget, std::move(sink_request),
-      std::move(private_request), std::move(client),
-      std::move(display_request));
+      std::move(frame_sink_data_->pending_compositor_frame_sink_request),
+      std::move(client), std::move(display_request));
 
   if (window_->parent()) {
     ServerWindow* root_window = window_->GetRoot();
@@ -64,20 +56,12 @@ void ServerWindowCompositorFrameSinkManager::CreateCompositorFrameSink(
   cc::FrameSinkId frame_sink_id(WindowIdToTransportId(window_->id()), 0);
 
   if (!frame_sink_data_)
-    frame_sink_data_ = base::MakeUnique<CompositorFrameSinkData>();
+    CreateCompositorFrameSinkData();
 
   frame_sink_data_->frame_sink_id = frame_sink_id;
-  cc::mojom::MojoCompositorFrameSinkPrivateRequest private_request;
-  if (frame_sink_data_->pending_compositor_frame_sink_request.is_pending()) {
-    private_request =
-        std::move(frame_sink_data_->pending_compositor_frame_sink_request);
-  } else {
-    private_request =
-        mojo::MakeRequest(&frame_sink_data_->compositor_frame_sink);
-  }
-
   window_->delegate()->GetDisplayCompositor()->CreateCompositorFrameSink(
-      frame_sink_id, std::move(request), std::move(private_request),
+      frame_sink_id, std::move(request),
+      std::move(frame_sink_data_->pending_compositor_frame_sink_request),
       std::move(client));
 
   if (window_->parent()) {
@@ -91,13 +75,8 @@ void ServerWindowCompositorFrameSinkManager::CreateCompositorFrameSink(
 
 void ServerWindowCompositorFrameSinkManager::AddChildFrameSinkId(
     const cc::FrameSinkId& frame_sink_id) {
-  if (frame_sink_data_) {
-    frame_sink_data_->compositor_frame_sink->AddChildFrameSink(frame_sink_id);
-    return;
-  }
-  frame_sink_data_ = base::MakeUnique<CompositorFrameSinkData>();
-  frame_sink_data_->pending_compositor_frame_sink_request =
-      mojo::MakeRequest(&frame_sink_data_->compositor_frame_sink);
+  if (!frame_sink_data_)
+    CreateCompositorFrameSinkData();
   frame_sink_data_->compositor_frame_sink->AddChildFrameSink(frame_sink_id);
 }
 
@@ -107,6 +86,13 @@ void ServerWindowCompositorFrameSinkManager::RemoveChildFrameSinkId(
   frame_sink_data_->compositor_frame_sink->RemoveChildFrameSink(frame_sink_id);
 }
 
+void ServerWindowCompositorFrameSinkManager::ClaimTemporaryReference(
+    const cc::SurfaceId& surface_id) {
+  if (!frame_sink_data_)
+    CreateCompositorFrameSinkData();
+  frame_sink_data_->compositor_frame_sink->ClaimTemporaryReference(surface_id);
+}
+
 void ServerWindowCompositorFrameSinkManager::OnRootChanged(
     ServerWindow* old_root,
     ServerWindow* new_root) {
@@ -123,6 +109,13 @@ void ServerWindowCompositorFrameSinkManager::OnRootChanged(
   }
 }
 
+void ServerWindowCompositorFrameSinkManager::CreateCompositorFrameSinkData() {
+  DCHECK(!frame_sink_data_);
+  frame_sink_data_ = base::MakeUnique<CompositorFrameSinkData>();
+  frame_sink_data_->pending_compositor_frame_sink_request =
+      mojo::MakeRequest(&frame_sink_data_->compositor_frame_sink);
+}
+
 CompositorFrameSinkData::CompositorFrameSinkData() {}
 
 CompositorFrameSinkData::~CompositorFrameSinkData() {}