Display Compositor: Allocate LocalFrameId in client.

services/ui/public/cpp/window_compositor_frame_sink.cc

Index: services/ui/public/cpp/window_compositor_frame_sink.cc
diff --git a/services/ui/public/cpp/window_compositor_frame_sink.cc b/services/ui/public/cpp/window_compositor_frame_sink.cc
index 3249087189577c58dd353e56662d1ff4d0551a05..d75665004f61497d7f4ecf8e2471bb068fa84def 100644
--- a/services/ui/public/cpp/window_compositor_frame_sink.cc
+++ b/services/ui/public/cpp/window_compositor_frame_sink.cc
@@ -65,7 +65,17 @@ void WindowCompositorFrameSink::SubmitCompositorFrame(
   DCHECK(thread_checker_->CalledOnValidThread());
   if (!compositor_frame_sink_)
     return;
-  compositor_frame_sink_->SubmitCompositorFrame(std::move(frame));
+
+  gfx::Size frame_size = last_submitted_frame_size_;
+  if (!frame.render_pass_list.empty())
+    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(