Mus-WS / Aura-Mus: Propagate cc::LocalSurfaceId through WindowData

services/ui/public/interfaces/window_tree_constants.mojom

Index: services/ui/public/interfaces/window_tree_constants.mojom
diff --git a/services/ui/public/interfaces/window_tree_constants.mojom b/services/ui/public/interfaces/window_tree_constants.mojom
index 19a5fdf11af87d167694eca94c9d0d2ca02cb768..2e4bc1446d6a9b2f9546e565fcc98547007236d3 100644
--- a/services/ui/public/interfaces/window_tree_constants.mojom
+++ b/services/ui/public/interfaces/window_tree_constants.mojom
@@ -4,6 +4,7 @@
 
 module ui.mojom;
 
+import "cc/ipc/local_surface_id.mojom";
 import "ui/gfx/geometry/mojo/geometry.mojom";
 
 // Contains state of a single window.
@@ -20,6 +21,9 @@ struct WindowData {
 
   gfx.mojom.Rect bounds;
 
+  // The LocalSurfaceId that the window should use to render the first frame.
+  cc.mojom.LocalSurfaceId? local_surface_id;
+
   // Arbitrary key/value pairs. The interpretation of these is left to the
   // client. See SetWindowProperty() for more information.
   map<string, array<uint8>> properties;