Allow querying for multiple uids in NetworkCycleDataForUidLoader.

- since we might want to get aggregated usage data for multiple uids,
change the implementation to allow adding multiple uids instead of
always querying for a single uid.

Change-Id: I26ba07042f8a0a0800e6d0ad0938da70691c3500
Fixes: 122200400
Test: make RunSettingsLibRoboTests
2 files changed