Resolved incoming pairing/connection issue

Sending bond_state_changed and adapter_properties_cb concurrently was
causing a race condition, which resulted in the BOND_STATE_CHANGED intent not
being sent. This caused the Settings to not show the newly bonded
device. This has been resolved by letting BondStateMachine manage
the mBondedDevices

Change-Id: Ieba39602436370fd9a87c3aa938ff3bd724c68cf