This revision is from docker_1.5 branch, because we don't want to
introduce user namespace in docker 1.5, but fix for --pid=host is
needed.
Fixes#10303
Signed-off-by: Alexander Morozov <lk4d4@docker.com>
Upstream-commit: fd2d45d7d465fe02f159f21389b92164dbb433d3
Component: engine