title: Test Android Activity with different Application class
body: <p>I´m looking for a way to test an Activity with JUnit4 and the ActivityTestRule, but with a different application class (e.g. mocked or inherited). I was able to get this for library projects using the manifest merge and tools:replace="android:name" on the application tag in the androidTest/AndroidManifest.xml. This however does not work for applications.</p>
  
  <p>Any ideas how this can be done?</p>