Check_MK Werk 5976: Fixed possible "AttributeError" exception on custom graph list page

ID: 5976 Title: Fixed possible "AttributeError" exception on custom graph list page Component: Multisite Level: 1 Class: Bug fix Version: 1.6.0i1 When a user opened up the custom graph list page while another user had a custom graph that was not published to other users, this lead to an exception on this page.