Move stats map A/B dump to NetworkStatsService

Map status dump will do access check if map is null.
This could show different message from the current dump output.

Information in map content dump does not change
$ dumpsys connectivity trafficcontroller
....
      mStatsMapA:
      ifaceIndex ifaceName tag_hex uid_int cnt_set rxBytes rxPackets txBytes txPackets
      20 wlan0 0x0 1051 0 144 2 312 4
      10 rmnet_data0 0x0 0 0 0 0 48 1
      20 wlan0 0x0 0 0 0 0 136 2
      20 wlan0 0xffffff82 1051 0 144 2 312 4

      mStatsMapB:
      ifaceIndex ifaceName tag_hex uid_int cnt_set rxBytes rxPackets txBytes txPackets
....

$ dumpsys netstats
....
  mStatsMapA:
    ifaceIndex ifaceName tag_hex uid_int cnt_set rxBytes rxPackets txBytes txPackets
    20 wlan0 0x0 1051 0 144 2 312 4
    10 rmnet_data0 0x0 0 0 0 0 48 1
    20 wlan0 0x0 0 0 0 0 136 2
    20 wlan0 0xffffff82 1051 0 144 2 312 4
  mStatsMapB:
    ifaceIndex ifaceName tag_hex uid_int cnt_set rxBytes rxPackets txBytes txPackets
....

Bug: 217624062
Test: dumpsys netstats, dumpstate, atest NetworkStatsServiceTest

Change-Id: Ifbd45f0ad6dd9c519a15a7680cf0ea99fb5f5dcf
4 files changed