Cache the last connection timestamp in scorecard

Caches the timestamp of the last successful L2 connection.
This information will be used to detect frequent disconnects.

Bug: 139287182
Test: atest FrameworksWifiTests

Change-Id: I6ce7ed07f552a4980a0aa13a96a0d5ed5934dd53
4 files changed
tree: 0ad8ec9740dc364a9683bc535813581b5f8a05c1
  1. service/
  2. PREUPLOAD.cfg