Author: Paul Holden
MDL-37802 repository: return error if unzipping files fails.
For instance, when a user tried to unzip a password protected zip
archive using the file manager.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=c98428aab38a68a8502024e09c2b9bf87ddce91b
http://github.com/moodle/moodle/commit/c98428aab38a68a8502024e09c2b9bf87ddce91b
+ 3.9 en [cannotunzipextractfileerror,core_repository]