Fix issue #899198 MODE_RINGER_STREAMS_AFFECTED does not restore volumes correctly

The problem is that setRingerModeInt() does not handle streams not affected by ringer mode: when enabling "Alarm in silent mode" while in silent mode, setRingerModeInt is called after alarm streamis removed from ringer mode affected streams, and nothing is done.

The fix constists in also processing streams that are not affected by ringer mode and to restore last audible volume for them. It does not arm reapplying the volume for streams the are never affected by ringer mode as we don't do this very often.

The other problem noted in the bug report (ringer volume always restored to non zero value when exiting silent mode even if set to zero before) is also fixed: a new parameter is added to setIndex() and setStreamVolumeInt() to explicitely request to store the volume index as last audible instead of doing it automatically if index > 0.