* A dependent job was requeued even if it wasn't part of the queue
before. The code relied on dependent jobs being already enqueued;
but that cannot be guaranteed.
* If a job failed, its dependent jobs are now also set to failed, so
that they won't be requeued at a later point.
* This caused some of the "Launching xxx failed: Operation not allowed"
messages in the boot process. Those actually weren't harmless, and
could mess up the natural job order.