* Fix of the issue that incoming call triggered
handsfree ringing which didn't stop after
calling side hung up.
* Cleanup of several places in code, minor
bluetooth <-> cellular integration refactor.
Fix of the issue that connecting or
disconnecting BT device while call
was in progress resulted in no sound
being heard anywhere due to audio
routing being stopped when HFP device
disconnected.
Additionally minor code cleanup.
Fix of the issue that after disconnecting
BT A2DP device during music playback
and reconnecting it without leaving
music player app the sound was not
audible anywhere.
Additionally unified behaviour of music
playback on connection/disconnection
of audio devices.
Set of fixes for Bluetooth volume control issues:
* split OS volume from A2DP device volume;
* added translations for additional popup required
to indicate what volume is being set;
* fixed issue that on some devices setting the lowest
volume level would set the highest in reality;
* fixed Bluetooth auto-turnoff functionality;
* minor code cleanup.
Bluetooth device volume control can be set by Pure Phone
while paired and is in A2DP mode. Temporarly disabled
HSP since it's not fully working and causing control issues.
To be able to handle properly the Bluetooth stack we need to
get rid of doubled FreeRTOS task and do refactor of
the whole BT section. This is first part of refactor and it
includes integrating run loop into our worker and unifying
namespaces