Make Mozart view manager use the new compositor.

mojo/services/ui/views/interfaces/layouts.mojom

Index: mojo/services/ui/views/interfaces/layouts.mojom
diff --git a/mojo/services/ui/views/interfaces/layouts.mojom b/mojo/services/ui/views/interfaces/layouts.mojom
index 7a6a1779604fc2424cc50fd5d89d21f98462cadc..f9831cc45b275df6c5bfe9157a63b730cebc8304 100644
--- a/mojo/services/ui/views/interfaces/layouts.mojom
+++ b/mojo/services/ui/views/interfaces/layouts.mojom
@@ -6,7 +6,7 @@
 module mojo.ui;
 
 import "mojo/services/geometry/interfaces/geometry.mojom";
-import "mojo/services/surfaces/interfaces/surface_id.mojom";
+import "mojo/services/gfx/composition/interfaces/scene_token.mojom";
 
 // Box constraints for layout.
 //
@@ -65,9 +65,15 @@ struct ViewLayoutParams {
 
 // Layout information for a view.
 struct ViewLayoutInfo {
-  // The view's surface id for composition by the parent.
-  mojo.SurfaceId surface_id;
+  // The view's scene token for composition by the parent.
+  mojo.gfx.composition.SceneToken scene_token;
 
   // The actual size of the view in device pixels.
   mojo.Size size;
 };
+
+// Result of a view layout request.
+struct ViewLayoutResult {
+  // The actual size of the view in device pixels.
+  mojo.Size size;
+};