Currently, we only count add tethering traffic to per-UID
stats, but not to total data usage (i.e., dev and XT stats). This
is correct for software tethering, because all software forwarded
packets are already included in interface counters, but it is
incorrect for hardware offload, because such packets do not
increment interface counters.
To fix this:
1. Add an argument to ITetheringStatsProvider#getTetherStats to
indicate whether per-UID stats are requested. For clarity,
define integer constants STATS_PER_IFACE and STATS_PER_UID
to represent these operations.
2. Make NetdTetheringStatsProvider return stats only if per-UID
stats are requested. (Otherwise tethering traffic would be
double-counted).
3. Make OffloadController's stats provider return the same
stats regardless of whether per-UID stats were requested or
not.
4. Make NetworkStatsService add non-per-UID tethering stats to
the dev and XT snapshots. The per-UID snapshots were already
correctly adding in per-UID stats.
(cherry picked from commit 5356a35c3bcfcdf2d184c620af6bfbf9bddf35c5)
Bug: 29337859
Bug: 32163131
Test: runtest frameworks-net
Test: runtest frameworks-telephony
Change-Id: I325b13d50e88841dfb0db4c35e7e27f163ee72fe
Merged-In: I4e8e923d68dce1a4a68608dbd6c75a91165aa4ee
f1912ca49a