tree 3e5f7910ed60b95469734b0852bd6918fccf4667
parent 744c5f217e4271a701a80b01c393bd828132cdbf
author calvinpan <calvinpan@google.com> 1541034570 +0800
committer Calvin Pan <calvinpan@google.com> 1542009975 +0000

Add a url for getting the current APN list

There has three steps:
1. Query the APN based on carrier ID and fall back to query { MCC, MNC, MVNO }.
2. If can't find the current APN, then query the parent APN. Query based on
   MNO carrier id and { MCC, MNC }.
3. else return empty cursor

Bug: 115709816
Test: run TelephonyProviderTest
Change-Id: I573e5279ee37e9325880fb1527a698da7e24fb9f
Merged-in: I573e5279ee37e9325880fb1527a698da7e24fb9f