Reinstate new VPN uid filtering unit tests

Mock out PackageManager and returns correct information corresponding
to the test app package itself.

Test: atest --generate-new-metrics 10 com.android.server.ConnectivityServiceTest
Bug: 114231106
Bug: 130397860
Change-Id: Ib921700eda417f411d7a2c77c1140fba9ab50bbb
1 file changed