MediaPlayer2: add fallback logic for ringtone default actual uri.

Also, private API, getAuthorityWithoutUserId(), usage is replaced
with RingtoneManager.getDefaultType(). The code is using authority
to check if the uri is ringtone default uri, but it can be also checked
with getDefaultType() since it returns -1 for non ringtone default uri.

Test: MediaPlayer2Test
Bug: 112767549
Change-Id: I4c41314364e8bc398ffe75cb0ecc20a06a4502c8