CHROMIUM: test_job_process: Really wait for child to stop

When removing some excess sleeps and improper polling loops, I see test
failures like:

...ensure multi process output logged
BAD: wrong content in file 0x5b11d43d6810 (output), expected 'started

' got 'started'
	at tests/test_job_process.c:4865 (test_spawn).

This is because we didn't actually wait for our child to run before we
wait on (and process) its log output. The child is SIGSTOP'ing itself:

	case TEST_OUTPUT_WITH_STOP:
	...
		 raise (SIGSTOP);

So we should wait on that.

BUG=b:232122437
TEST=cros_run_unit_tests

Change-Id: I9e106d8be098ebc241b26a3348ce171b3ac5e04a
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/upstart/+/5446406
Tested-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Allen Webb <allenwebb@google.com>
Commit-Queue: Brian Norris <briannorris@chromium.org>
1 file changed