tree 55348a815d3cacf0ce851246c7930f258939d096
parent c00b1067a05116548a0883e1400a1c4715078797
author Lorenzo Colitti <lorenzo@google.com> 1439275379 +0900
committer Lorenzo Colitti <lorenzo@google.com> 1439275379 +0900

Don't attempt to stop the receive thread if we never started it.

If socket initialization fails, DhcpState#exit will call
mReceiveThread#stop and crash the system with an NPE. Make sure
we don't do that if mReceiveThread is null, and properly null it
out when exiting.

Bug: 23088314
Change-Id: I4378d8280f9d8588f5eaa8bd7ade61beab1c3ce2