Don't leak AlertContainer refs when tracking progress of tasks
Don't leak AlertContainer refs when tracking progress of tasks

In khm_nc_track_progress_of_this_task(), the AlertContainer object
used for tracking the task may be left with extra references in some
cases.  Don't track references manually and use AutoRef<> objects.

Change-Id: Ib39886a7b0688d16b9fb96199112de274ff84d21

secure-endpoints/netidmgr,secure-endpoints/netidmgr,secure-endpoints/netidmgr,secure-endpoints/netidmgr,secure-endpoints/netidmgr