Display Compositor: Allocate LocalFrameId in client.

ui/aura/mus/window_compositor_frame_sink.cc

Index: ui/aura/mus/window_compositor_frame_sink.cc
diff --git a/ui/aura/mus/window_compositor_frame_sink.cc b/ui/aura/mus/window_compositor_frame_sink.cc
index 1490457984d89ace1218ba6eede5a6ce22928b8c..eabe858e34eff40a4b960c8f271e62542535b734 100644
--- a/ui/aura/mus/window_compositor_frame_sink.cc
+++ b/ui/aura/mus/window_compositor_frame_sink.cc
@@ -64,14 +64,23 @@ void WindowCompositorFrameSink::SubmitCompositorFrame(
   DCHECK(thread_checker_->CalledOnValidThread());
   if (!compositor_frame_sink_)
     return;
-  compositor_frame_sink_->SubmitCompositorFrame(std::move(frame));
+
+  gfx::Size frame_size;
+  if (!frame.render_pass_list.empty())

[sadrul, 2016/11/22 19:22:25]

Is it valid for a frame to have no render-pass? (applies to all the rest of the
places this is checked)

[Fady Samuel, 2016/11/22 19:24:38]

The pattern of submitting an empty CompositorFrame is used in some places to
evict resources used by the previous frame.

[sadrul, 2016/11/22 19:25:48]

I see. Should that reset the frame/frame-sink size and id?

+    frame_size = frame.render_pass_list[0]->output_rect.size();
+  if (!local_frame_id_.is_valid() || frame_size != last_submitted_frame_size_)
+    local_frame_id_ = id_allocator_.GenerateId();
+
+  compositor_frame_sink_->SubmitCompositorFrame(local_frame_id_,
+                                                std::move(frame));
+
+  last_submitted_frame_size_ = frame_size;
 }
 
 WindowCompositorFrameSink::WindowCompositorFrameSink(
     scoped_refptr<cc::ContextProvider> context_provider,
     gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager,
-    mojo::InterfacePtrInfo<cc::mojom::MojoCompositorFrameSink>
-        compositor_frame_sink_info,
+    cc::mojom::MojoCompositorFrameSinkPtrInfo compositor_frame_sink_info,
     cc::mojom::MojoCompositorFrameSinkClientRequest client_request)
     : cc::CompositorFrameSink(std::move(context_provider),
                               nullptr,