Merge changes I8056830b,I1407644e,Ie32c8651,I60929eec,I06cd226c, ...

* changes:
  List network permissions in dumpsys netd.
  Close sockets when changing network permissions.
  Add general /proc/sys/net/ipv[46]/{conf,neigh}/ interface
  Disable DAD for downstream interfaces when tethering
  Add tests for interface add/remove binder API
  Support adding/removing IPv4 and IPv6 addresses on interfaces
  Don't start tethering if IPv6 RPF is not supported.
  Enable IPv6 reverse path filtering.
  Allow networking on loopback in doze, standby, and powersave.
  Don't close loopback sockets when a VPN connects or entering doze.
  Make the socketDestroy tests use a fake tun interface.
  Add tetherApplyDnsInterfaces() binder interface.
  Parse IPv6 tethering counters.
  Add counters for IPv6 tethering.
  Refactor getTetherStats in preparation for IPv6 tether counters.
  More test coverage for tethering counter parsing.
  Add a test for NatController.
  Add a test for getTetherStats.
  Setup interfaces for IPv6 tethering
  Listen to xt_quota2 kobject event for quota
  Verify expectations better in SockDiagTest.
  Don't fail the test if the iptables lock is held.
  Silence spammy iptables rule at boot.