Author: Zig Tan
MDL-61568 repository_webdav: Implement null privacy provider
http://git.moodle.org/gw?p=moodle.git;a=commit;h=65f6e6ad896fceb98b94f0561eae851a3cff2f94
http://github.com/moodle/moodle/commit/65f6e6ad896fceb98b94f0561eae851a3cff2f94
+ 3.3 en [privacy:metadata,repository_webdav]