MCC detection fixes for CountryDetector

- Don't get and cache phone tpe at the initialization time.  At this point
TelephonyManager is probably not ready yet.

- Refresh MCC whenever we get the service state changed callback, even when
the state hasn't actually changed, in order to make sure we get refresh
country properly when MCC changes.

- Also remove the initialization of mPhoneStateListener, which prevented us from
registering phone state listener properly.

- Also fix tests which were already failing.

Bug 5670680

Change-Id: Id45abeba1b1e843053ac2c946861b439ca568de4