WIP: Propagate SurfaceID up window tree hierarchy

services/ui/ws/window_tree_host_factory.cc

Index: services/ui/ws/window_tree_host_factory.cc
diff --git a/services/ui/ws/window_tree_host_factory.cc b/services/ui/ws/window_tree_host_factory.cc
index e24fd082344eb3b1ecd64436b10b8edd3c3c86e0..e81a7e093e095b3bc799761429956471505ae9b3 100644
--- a/services/ui/ws/window_tree_host_factory.cc
+++ b/services/ui/ws/window_tree_host_factory.cc
@@ -4,7 +4,7 @@
 
 #include "services/ui/ws/window_tree_host_factory.h"
 
-#include "services/ui/surfaces/surfaces_state.h"
+#include "services/ui/surfaces/display_compositor.h"
 #include "services/ui/ws/display.h"
 #include "services/ui/ws/display_binding.h"
 #include "services/ui/ws/window_server.h"
@@ -15,8 +15,8 @@ namespace ws {
 WindowTreeHostFactory::WindowTreeHostFactory(WindowServer* window_server,
                                              const UserId& user_id)
     : window_server_(window_server), user_id_(user_id) {
-  platform_display_init_params_.surfaces_state =
-      window_server_->GetSurfacesState();
+  platform_display_init_params_.display_compositor =
+      window_server_->GetDisplayCompositor();
 }
 
 WindowTreeHostFactory::~WindowTreeHostFactory() {}