[MS68.3] Address comments at aosp/1958144

Test: atest TrafficStatsTest NetworkUsageStatsTest FrameworksNetTests
Bug: 204830222

(cherry-picked from ag/16813003)

Change-Id: I5a54b44294021d64d8506eeb570db0db8544472a
Merged-In: I5a54b44294021d64d8506eeb570db0db8544472a
5 files changed