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Git commits in Moodle 2.5.6 by Jonathon Fowler
commit 0859a464cb1a64a745e1b8ec82aec01dbf3a2107 Author: Jonathon Fowler <fowlerj@usq.edu.au> Date: Tue, 15 Apr 2014 12:18:55 +0800 Tag: v2.5.6 MDL-44270 files: handle drag-drop js error when event has null types