Mustash: Ensure surfaces submitted to Mus by WM and embedders contain Surfaces with embeded content.

services/ui/ws/server_window_compositor_frame_sink_manager.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "services/ui/ws/server_window_compositor_frame_sink_manager.h"
 
 #include "cc/ipc/display_compositor.mojom.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
 #include "services/ui/ws/ids.h"
 #include "services/ui/ws/server_window.h"
@@ skipping 10 matching lines @@
           0) {}
 
 ServerWindowCompositorFrameSinkManager::
     ~ServerWindowCompositorFrameSinkManager() {
 }
 
 bool ServerWindowCompositorFrameSinkManager::ShouldDraw() {
   if (!waiting_for_initial_frames_)
     return true;
 
   waiting_for_initial_frames_ = !IsCompositorFrameSinkReadyAndNonEmpty(

[sky, 2016/12/16 21:50:29]

Can we replace waiting_for_initial_frames_ with
IsCompositorFrameSinkReadyAndNonEmpty(DEFAULT)?

[mfomitchev, 2016/12/23 00:03:49]

Actually, it seems like currently this is always false (with or without my CL),
because it is initialized to false unless ui::mojom::kWaitForUnderlay_Property
is set, and that is never set. I've added a TODO to  clean this up. We could in
theory delete a bunch of code here. Will confirm with fsamuel and do it in a
separate CL if that's okay.

-                                    mojom::CompositorFrameSinkType::DEFAULT) ||
-                                !IsCompositorFrameSinkReadyAndNonEmpty(
-                                    mojom::CompositorFrameSinkType::UNDERLAY);
+      mojom::CompositorFrameSinkType::DEFAULT);
   return !waiting_for_initial_frames_;
 }
 
 void ServerWindowCompositorFrameSinkManager::CreateDisplayCompositorFrameSink(
     gfx::AcceleratedWidget widget,
     cc::mojom::MojoCompositorFrameSinkRequest request,
     cc::mojom::MojoCompositorFrameSinkClientPtr client) {
   CreateCompositorFrameSinkInternal(mojom::CompositorFrameSinkType::DEFAULT,
                                     widget, std::move(request),
                                     std::move(client));
@@ skipping 153 matching lines @@
 
 CompositorFrameSinkData& CompositorFrameSinkData::operator=(
     CompositorFrameSinkData&& other) {
   latest_submitted_surface_id = other.latest_submitted_surface_id;
   compositor_frame_sink = std::move(other.compositor_frame_sink);
   return *this;
 }
 
 }  // namespace ws
 }  // namespace ui