Define an attenuation threshold under which the
MODIFY_AUDIO_SETTINGS permission is required to adjust volume.
Verify permission at the interface of audio service, and
propagate this information so its used when getting a valid
index during a volume adjustment or set.
Make the audio service dump display the min index when it
differs from the normal min index.
Enforcement is only for STREAM_ALARM.
Bug: 137015603
Test: use POC app in bug, verify ALARM volume not at 1 with \
adb shell dumpsys audio
Change-Id: I7ccb50e314bb0e27ba25346eab9cdd3e4dd1dceb
803c3158b1