[IMPR] AudioService: VolumeGroupState: improve implementation

Bug: 260298113
Test: atest AudioVolumeGroupTest

-User VolumeStreamState.class to synchronize to avoid deadlock
-Profilization & user switch management
	-Aligned with stream: music settings are preserved from
            one user to the next
        -if associated to stream, use same System Settings
-Mute management: only group with zero min index are mutable

Signed-off-by: Francois Gaffie <francois.gaffie@renault.com>
Change-Id: I9c8575c417df7267d81f4346bc66d476157e6d7d
Merged-In: I9c8575c417df7267d81f4346bc66d476157e6d7d