title: As a system app, kill another process, by package name
body: <p>I'm developing a watchdog system service on android.
  In case I detect that some foreground app is blocked/halted I want to force restart of the app.</p>
  
  <p>I've already tried kill background app, with no success (as i'm trying to kill a foreground app).
  also, via exec(adb shell su killall com.package.name) crashes with no permission, as i'm "just" system, not rooted device.</p>