code: public void setIsDeviceLocked(int userId, boolean isLocked) {
      if (isLocked) {
        deviceLockedForUsers.add(userId);
      } else {
        deviceLockedForUsers.remove(userId);
      }
    }
docs: For tests on Android >= L MR1, sets the value to be returned by {@link #isDeviceLocked(int)}.
  
  @see #isDeviceLocked(int)