Author: Mathew May
MDL-44484 admin: Theme can be null and create user
http://git.moodle.org/gw?p=moodle.git;a=commit;h=e6ce167bb7dfb42ad77f3d579dfdbeade970432b
http://github.com/moodle/moodle/commit/e6ce167bb7dfb42ad77f3d579dfdbeade970432b
+ 3.7 en [invalidtheme,tool_uploaduser]
+ 3.7 en [notheme,tool_uploaduser]
+ 3.7 en [userthemesnotallowed,tool_uploaduser]
- 3.7 en [invalidfieldvalue,core_error]
- 3.7 en [invalidtheme,core_error]