Permit minijail0 callers to act as init to jailed processes

In particular, sometimes we jail processes in init scripts.  In those
cases, it is logical to have the init process act as the init process
for the jailed process.  This is accomplished by having minijail0 exit
immediately after forking.

BUG=chromium:298341
TEST=After this change, observed that minijail exits immediately,
leaving its child process in the hands of the parent.

Change-Id: I66a5fb35bfabc37d6bf2d03b79daa11b10b29ad5
Reviewed-on: https://chromium-review.googlesource.com/175600
Tested-by: Christopher Wiley <wiley@chromium.org>
Reviewed-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Commit-Queue: Christopher Wiley <wiley@chromium.org>
1 file changed