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Git commits in Moodle 3.1.5 by Jonathan Champ
commit e3d53b99aa18b60ca1ac3a9451c36ec3d7c5e78b Author: Jonathan Champ <jonathan_champ@ncsu.edu> Date: Sat, 17 Dec 2016 01:20:45 +0800 Tag: v3.1.5 MDL-57427 cache: Use perfdebug only when enabled