Git commits in Moodle 3.1.x by Jerome Mouneyrac

commit b406f53662ebeec5f7e497e890e8d9d44667485d
Author: Jerome Mouneyrac <jerome@mouneyrac.com>
Date:   Tue, 05 Aug 2014 18:30:29 +0800
Tag:    v3.1.1

MDL-46682 auth/db: IN clause crashes when too many users to sync