Audio mode may not be useful in OboeTester

In OboeTester, it is possible to set audio mode from the main activity. However, the framework will reset the mode to NORMAL if the mode owner's activity is gone, which is 5 or 6 seconds. That indicates in most case, after setting the mode, such as IN_COMMUNICATION, IN_CALL, etc and then goes to other activity, the mode may not really affect the test result as it is reset.