*really*, *really* ensure Jobs are not added to the session until fully populated

Same idea as commits 6f8300e and a38896c... I think we got them all this
time.

Bug: 896622
Change-Id: I128bbaab19b7b69d7bcf1456d9f3b95be155b4cb
Automatic commit of package [beaker] release [0.11.1-1].
Merge branch 'release-0.11'