Run cgroups cleanup code in WatchDog.
After CL:45672, the watchdog process doesn't run cgroups cleanup code. This
means that orphaned child processes are left around when you press the 'stop'
button on a builder.
BUG=chromium:223044
TEST=Run test case where child process switched the sid and verify that this
child gets killed.
Change-Id: I367425df849a7ef9ce38cafb1998e72b34b19eb7
Previous-Reviewed-on: https://gerrit.chromium.org/gerrit/47188
(cherry picked from commit 2852ba2c23eb6809f0b97f7abedecfb2c63561a2)
Reviewed-on: https://gerrit.chromium.org/gerrit/49737
Tested-by: David James <davidjames@chromium.org>
Reviewed-by: Ryan Cui <rcui@chromium.org>
3 files changed
