title: Android UI test Fingerprint with Espresso
body: <p>I have an Android fingerprint implementation working and I was looking to add UI tests with Espresso. One problem I can't find a solution to is how to emulate the scanning of a finger. There is an adb command
  <code>adb -e emu finger touch</code> which should work on emulators. </p>
  
  <p>Any idea on how to integrate something like that with Espresso?</p>