rails3: fixes in notification policy setup_for

Change-Id: Ib8738dd308bd159d7d7b60aa334577e011757c37
Reviewed-on: https://gerrit.instructure.com/29587
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Jon Willesen <jonw@instructure.com>
Product-Review: Jon Willesen <jonw@instructure.com>
QA-Review: Jon Willesen <jonw@instructure.com>