Split out DeathRecipient behavior

We can re-use this class to monitor client interface death as well from
the WifiStateMachine.

Bug: 30041062
Test: Can kill wificond underneath the framework with tethering on
      and still see tethering taken down.
Test: unittests pass

Change-Id: I4dd60bd8eb674fc06d5eb301b0d8f10218126383
2 files changed
tree: 827ce981241909960a67bb8e26ba9defcf9da523
  1. libwifi_hal/
  2. libwifi_system/
  3. service/
  4. tests/