log an error report to get a full stack trace of a broadcast policy error

refs gh-349

Change-Id: I04ab0d1dc666daacf6a35f14d6e7d70069d185b1
Reviewed-on: https://gerrit.instructure.com/33796
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Rob Orton <rob@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>