Make RendererCompositorFrameSink derive from ClientCompositorFrameSink

ui/aura/mus/window_port_mus.cc

Index: ui/aura/mus/window_port_mus.cc
diff --git a/ui/aura/mus/window_port_mus.cc b/ui/aura/mus/window_port_mus.cc
index 14ae20a368daca4d74ce4909e70545b361551f90..870420dd05fd91520d110f22332163d8ea50dab5 100644
--- a/ui/aura/mus/window_port_mus.cc
+++ b/ui/aura/mus/window_port_mus.cc
@@ -105,8 +105,8 @@ WindowPortMus::RequestCompositorFrameSink(
       mojo::MakeRequest(&client);
   constexpr bool enable_surface_synchronization = true;
   auto compositor_frame_sink = base::MakeUnique<viz::ClientCompositorFrameSink>(
-      std::move(context_provider), gpu_memory_buffer_manager,
-      std::move(sink_info), std::move(client_request),
+      std::move(context_provider), nullptr, gpu_memory_buffer_manager, nullptr,
+      nullptr, std::move(sink_info), std::move(client_request),

[sadrul, 2017/05/29 16:56:47]

Can you add comments for the null things? e.g.

  std::move(context_provider), nullptr /* worker_context_provider */,
  gpu_memory_buffer_manager, nullptr /* shared_bitmap_manager */,

etc. That makes it easier to read the code.

       enable_surface_synchronization);
   window_tree_client_->AttachCompositorFrameSink(
       server_id(), std::move(sink_request), std::move(client));