Could not enable data connection

Could not enable the default type APN in below case:
1. Default apn exists, connect wifi
2. Delete default apn
3. Disconnect wifi

enableApnType won't reactivate default apn type when no
default apn exists. Add default apn criterium to avoid this.

Change-Id: Ic8699669e576e5d2140852f359e34ed6c3275633