Marina has attached her patch to the issue. You can use git to apply it to your moodle instance (you will want to use a test instance at first)
git init .
git pull git://github.com/marinaglancy/moodle.git MDL-34161-31
You'll need to read the comments to figure out what to do next, sounds like it is blocked by https://tracker.moodle.org/browse/MDL-36580