Author: Zig Tan
MDL-58702 backup: Fix restoration of role mappings labels
Changes:
- Add logic to retrieve all the existing current roles.
- Apply the backup's role shortname by matching on the archetype.
- Added backup lang string 'undefinedrolemapping'.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=e275b0c4a63b35dac1145e35501ce45f9cf24058
http://github.com/moodle/moodle/commit/e275b0c4a63b35dac1145e35501ce45f9cf24058
+ 3.5 en [undefinedrolemapping,core_backup]