Reify view ownership as a message pipe.

examples/ui/spinning_cube/spinning_cube_app.h

Index: examples/ui/spinning_cube/spinning_cube_app.h
diff --git a/examples/ui/spinning_cube/spinning_cube_app.h b/examples/ui/spinning_cube/spinning_cube_app.h
index e658717afd3fed5caeb0fe6ab78043c3ce247855..5aa3f5f8e428cb4608d69b4b26a360ec2b21dc24 100644
--- a/examples/ui/spinning_cube/spinning_cube_app.h
+++ b/examples/ui/spinning_cube/spinning_cube_app.h
@@ -14,11 +14,11 @@ class SpinningCubeApp : public mojo::ui::ViewProviderApp {
   SpinningCubeApp();
   ~SpinningCubeApp() override;
 
-  bool CreateView(
+  void CreateView(
       const std::string& connection_url,
+      mojo::InterfaceRequest<mojo::ui::ViewOwner> view_owner_request,
       mojo::InterfaceRequest<mojo::ServiceProvider> services,
-      mojo::ServiceProviderPtr exposed_services,
-      const mojo::ui::ViewProvider::CreateViewCallback& callback) override;
+      mojo::ServiceProviderPtr exposed_services) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SpinningCubeApp);