Merge "Offload killProcessGroup to a worker thread" into nyc-dev am: d845a8b
am: 9e07071c

* commit '9e07071c67fad37070fb29a68a67595567567f36':
  Offload killProcessGroup to a worker thread

Change-Id: Ifb9222c45e4098fccc12fd5ec4c01cd8f0bce1cd