Fix AudioManagerTest to handle TVs that don't vibrate and lack ringer

functionality.

Details: Running AudioManagerTest fails because TVs don't have vibration
feature and setRingerMode is disabled in AudioService.java.  So skip
affected tests..

Previous CL comments are here:
https://googleplex-android-review.git.corp.google.com/#/c/582796/

Bug: 17547824
Change-Id: I1ec5d803e5a079225f63da5285985be6006c1de7