Author: Andrew Nicols
MDL-85816 core: Warn on /public URLs
http://git.moodle.org/gw?p=moodle.git;a=commit;h=cc7ab4ce226c9c286077b85eb42aa0fcf394e3a0
http://github.com/moodle/moodle/commit/cc7ab4ce226c9c286077b85eb42aa0fcf394e3a0
+ 5.1 en [wwwrootpublic,core_error]