* changes:
Allow Nullable Registered PLMN
Return the RPLMN from NetworkRegistrationInfo
Expose PreciseDataConnectionstate#getApnSetting()
Skip sanitizing location info for Null Barring CID
Remove BarringInfo#isServiceBarred()
Introduce a new RIL request constant to support getBarringInfo.
Update BarringInfo as Barring HAL date stuctures updated
Add a BARRING_TYPE_UNKNOWN for Unreported Barring
Add Callback to notify changes of barring status