Change mojo geometry structs from using type converters to StructTraits.

components/mus/public/cpp/lib/window_tree_client_impl.h

Index: components/mus/public/cpp/lib/window_tree_client_impl.h
diff --git a/components/mus/public/cpp/lib/window_tree_client_impl.h b/components/mus/public/cpp/lib/window_tree_client_impl.h
index 3cfdbef9dee99f16ac19b229f6da9aecf8623618..dc134672b006e86f5eaf70af9d9d50b38c76e907 100644
--- a/components/mus/public/cpp/lib/window_tree_client_impl.h
+++ b/components/mus/public/cpp/lib/window_tree_client_impl.h
@@ -196,12 +196,12 @@ class WindowTreeClientImpl : public WindowTreeConnection,
                          mojom::WindowDataPtr data,
                          bool drawn) override;
   void OnWindowBoundsChanged(Id window_id,
-                             mojo::RectPtr old_bounds,
-                             mojo::RectPtr new_bounds) override;
+                             const gfx::Rect& old_bounds,
+                             const gfx::Rect& new_bounds) override;
   void OnClientAreaChanged(
       uint32_t window_id,
-      mojo::InsetsPtr new_client_area,
-      mojo::Array<mojo::RectPtr> new_additional_client_areas) override;
+      const gfx::Insets& new_client_area,
+      mojo::Array<gfx::Rect> new_additional_client_areas) override;
   void OnTransientWindowAdded(uint32_t window_id,
                               uint32_t transient_window_id) override;
   void OnTransientWindowRemoved(uint32_t window_id,
@@ -244,7 +244,7 @@ class WindowTreeClientImpl : public WindowTreeConnection,
   // Overridden from WindowManager:
   void WmSetBounds(uint32_t change_id,
                    Id window_id,
-                   mojo::RectPtr transit_bounds) override;
+                   const gfx::Rect& transit_bounds) override;
   void WmSetProperty(uint32_t change_id,
                      Id window_id,
                      const mojo::String& name,