Git commits in Moodle 2.8.x by Jordi Pujol Ahulló

commit b94e9188e7d4f3083da793dcdc1801f71b0d13ce
Author: Jordi Pujol Ahulló <jordi.pujol@urv.cat>
Date:   Tue, 24 Mar 2015 18:15:46 +0800
Tag:    v2.8.6

MDL-49641 repository_dropbox: preventing poor performance.