fix selenium db synchronization for rails 3

Change-Id: Iacf7aedeb43472f945a6892b456076761c55c35b
Reviewed-on: https://gerrit.instructure.com/30092
Reviewed-by: Cody Cutrer <cody@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
Product-Review: James Williams  <jamesw@instructure.com>
QA-Review: James Williams  <jamesw@instructure.com>