code: public void checkActivities(boolean checkActivities) {
      ActivityThread activityThread = (ActivityThread) RuntimeEnvironment.getActivityThread();
      ShadowInstrumentation shadowInstrumentation =
          Shadow.extract(activityThread.getInstrumentation());
      shadowInstrumentation.checkActivities(checkActivities);
    }
docs: Set to true if you'd like Robolectric to strictly simulate the real Android behavior when
  calling {@link Context#startActivity(android.content.Intent)}. Real Android throws a
  {@link android.content.ActivityNotFoundException} if given
  an {@link Intent} that is not known to the {@link android.content.pm.PackageManager}
  
  By default, this behavior is off (false).
  
  @param checkActivities True to validate activities.