OnSubscriptionsChangedListenerHandler(Looper looper) is hidden, there is no way to pass a looper to it in the test. This change partially revert aosp/1340040 to fix hidden API dependency. And will use a different approach to address this problem in later stages. Test: atest NetworkStatsSubscriptionMonitorTest Bug: 204830222 Bug: 213280079 Change-Id: Ie17f04cd9f174f2895bde4607bbd7a9a92181a96