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

ui/aura/mus/window_port_mus.h

Index: ui/aura/mus/window_port_mus.h
diff --git a/ui/aura/mus/window_port_mus.h b/ui/aura/mus/window_port_mus.h
index e88b694694432e2114c78b695f36cd1a849eb9a0..bd2658fe3c4baec3624a9505ca91846950a5bfb0 100644
--- a/ui/aura/mus/window_port_mus.h
+++ b/ui/aura/mus/window_port_mus.h
@@ -23,6 +23,10 @@
 #include "ui/gfx/geometry/rect.h"
 #include "ui/platform_window/mojo/text_input_state.mojom.h"
 
+namespace ui {
+class Layer;
+}
+
 namespace aura {
 
 class PropertyConverter;
@@ -195,6 +199,10 @@ class AURA_EXPORT WindowPortMus : public WindowPort, public WindowMus {
 
   PropertyConverter* GetPropertyConverter();
 
+  // Used when this window is embedding a client. Updates the surface layer
+  // corresponding to the client with the new surface.
+  void UpdateSurfaceLayer(SurfaceInfo* surface_info);
+
   // WindowMus:
   Window* GetWindow() override;
   void AddChildFromServer(WindowMus* window) override;
@@ -243,6 +251,13 @@ class AURA_EXPORT WindowPortMus : public WindowPort, public WindowMus {
 
   Window* window_ = nullptr;
 
+  // Used when this window is embedding a client. Contains the client's content.

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

Could you isolate all the state related to embedding in its own class? That way
it's clear what is related to embedding as well as when there is an embedding.

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

Done.

+  std::unique_ptr<ui::Layer> surface_layer_;
+
+  // Serves as a parent of clipping_layer_, used for clipping the surface layer
+  // to the window bounds.
+  std::unique_ptr<ui::Layer> clipping_layer_;
+
   ServerChangeIdType next_server_change_id_ = 0;
   ServerChanges server_changes_;