Fatal error occurs when viewing report page

Log in as an admin. browse to "My profile" in the user menu (top right hand corner). Click on any of reports (besides 'Browser sessions') and check that you don't get the error "Call to a member function add() on a non-object" but instead see the report. Make sure that the breadcrumb starts off as [Home ► Dashboard ► My profile ► Reports ► [Report name] ]. Navigate to a student's profile. Click on any of reports and check that you don't get the error "Call to a member function add() on a non-object" but instead see the report. Make sure that the breadcrumb starts off as [Home  ► LL  ► Participants  ► [User's name]  ► Reports  ► [Report name] ]. Go to the student's full profile. Click on any of reports and check that you don't get the error "Call to a member function add() on a non-object" but instead see the report. Make sure that the breadcrumb starts off as [Home  ► Users  ► [User's name]  ► Reports  ► [Report name] ].