Author: Sara Arjona
MDL-63692 core_message: Add favourite conversations to Privacy API
http://git.moodle.org/gw?p=moodle.git;a=commit;h=16913e60b37bced2dfebc234624f28601d9018da
http://github.com/moodle/moodle/commit/16913e60b37bced2dfebc234624f28601d9018da
+ 3.6 en [privacy:metadata:core_favourites,core_message]