In the previous design of NSS and NPMS, those only had IMSI to identify
the cell network. Now the telephony has created the "subId" handle,
which is the preferred mechanism for identifying subscribers.
This commit adds NetworkStats support for subscriberId as a part of
the network identity key
Bug: 80526261
Test: atest NetworkTemplateTest NetworkStatsCollectionTest
NetworkStatsServiceTest NetworkIdentityTest
Ignore-AOSP-First: merge conflict resolutions
Change-Id: I8549b11d0fcfc5a9426724d6b90de27b707cb77c
1f788606a0