[SDL 0301] SDL Device Listener

[theresalech]

Proposal: SDL Device Listener

The SDL Android library relies on a complex multiplexing system that operates through a foreground service. This service is started based on the connection of the Media and Phone bluetooth profiles. Since SDL is set up in a way that the mobile device acts as the listening server of a bluetooth SPP connection, the router service must be started and wait for incoming connections without knowing if anything will connect to it. This leads to the service having to start in the foreground for all bluetooth connections. One possible way to avoid this is by introducing a new prerequisite before starting the router service. This is done by adding a new class called SDLDeviceListener that will be activated in the SDLBroadcastReceiver to decide if the router service should be started or not.

Review: smartdevicelink/sdl_evolution#1001