Make ApplicationRunner's ctor's ApplicationDelegate* argument an std::unique_ptr instead.

examples/audio_play_test/play_tone.cc

Index: examples/audio_play_test/play_tone.cc
diff --git a/examples/audio_play_test/play_tone.cc b/examples/audio_play_test/play_tone.cc
index 8b65ef68246644a4ad858d65f4d07156fa54056b..001f32e7f2f3bb36f9febd46f8190e51c74fa05f 100644
--- a/examples/audio_play_test/play_tone.cc
+++ b/examples/audio_play_test/play_tone.cc
@@ -243,6 +243,8 @@ void PlayToneApp::Cleanup() {
 }  // namespace mojo
 
 MojoResult MojoMain(MojoHandle app_request) {
-  mojo::ApplicationRunner runner(new mojo::media::audio::examples::PlayToneApp);
+  mojo::ApplicationRunner runner(
+      std::unique_ptr<mojo::media::audio::examples::PlayToneApp>(
+          new mojo::media::audio::examples::PlayToneApp()));
   return runner.Run(app_request);
 }