title: Reset app state between InstrumentationTestCase runs
body: <p>One of my QA engineers is supporting an app with a fairly large codebase and a lot of different SharedPreferences files. He came to me the other day asking how to reset the application state between test runs, as if it had been uninstalled-reinstalled. </p>
  
  <p>It doesn't look like that's supported by Espresso (which he is using) nor by the Android test framework natively, so I'm not sure what to tell him. Having a native method to clear all the different SharedPreferences files would be a pretty brittle solution. </p>
  
  <p>How can one reset the application state during instrumentation? </p>