Add test for CSM#[get|set]MobileDataPreferredUids

Bug: 171872461
Test: atest ConnectivityManagerTest
Original-Change: https://android-review.googlesource.com/1736504
Merged-In: I43dfb049c271602526fa3e89ebb91219c7785a21
Change-Id: I43dfb049c271602526fa3e89ebb91219c7785a21
1 file changed