Reify view ownership as a message pipe.

examples/ui/shapes/shapes_app.h

Index: examples/ui/shapes/shapes_app.h
diff --git a/examples/ui/shapes/shapes_app.h b/examples/ui/shapes/shapes_app.h
index 4aba71c6bdc422f25382f7ad3d949c795d59cd8e..d44c2d7d3b123e94f2080aee60b2a4eba41426c6 100644
--- a/examples/ui/shapes/shapes_app.h
+++ b/examples/ui/shapes/shapes_app.h
@@ -14,11 +14,11 @@ class ShapesApp : public mojo::ui::ViewProviderApp {
   ShapesApp();
   ~ShapesApp() 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(ShapesApp);