Author: Zig Tan
MDL-61567 mod_folder: Implement null provider mod_folder
http://git.moodle.org/gw?p=moodle.git;a=commit;h=5223ceed6b64ce5ccbb63fa0fac483fa2355abab
http://github.com/moodle/moodle/commit/5223ceed6b64ce5ccbb63fa0fac483fa2355abab
+ 3.3 en [privacy:metadata,mod_folder]