9c11e89fe2
Teach NetworkStats about "counter sets" coming from kernel, and use them to track usage in foreground/background. Add AID_NET_BW_ACCT to system_server so it can control counter sets. Move to composite key of NetworkIdentitySet, UID, set, and tag when recording historical usage. Persisting still clusters by identity, since that is heaviest object. Request async stats poll during systemReady() to bootstrap later delta calculations. Reset kernel counters when UID removed. Update various tests. Bug: 5105592, 5146067 Change-Id: Idabec9e3ffcaf212879821515602ecde0a03de8c