When you have several languages on the site and content classes that exists with more than one language, you will get some problems if you delete a language.

Steps to reproduce

Tested with a standard eZ Publish installation 3.9+

• Log in to the admin interface.
• Check that you have more than one language listed in the language list (/content/translations) that does not have any objects.
• Go to the view of a class (ex: /class/view/16)
• Edit and select "Another language" and select the language that do not have any objects.
• Go back to the language list and remove a language.

• Now, go back to the class list and try to edit the content class you changed previously and you'll get a error message:

( ! ) Fatal error: Call to a member function on a non-object in /var/www/ez392/kernel/classes/ezcontentclassnamelist.php on line 71