Undefined constants when submitting an online text assignment

1. Enable mod_assignment (Assignment 2.2)
2. Create a new Online text assignment
3. Login as a student and click "Add submission"

Expected

• You can submit any submission without error or notice

Actually

• The following notices appear when viewing the form and when submitting the assignment.

  Notice: Use of undefined constant FILE_INTERNAL - assumed 'FILE_INTERNAL' in /Users/fmc/code/php/repositories/im/moodle/mod/assignment/type/online/assignment.class.php on line 46

  Notice: Use of undefined constant FILE_EXTERNAL - assumed 'FILE_EXTERNAL' in /Users/fmc/code/php/repositories/im/moodle/mod/assignment/type/online/assignment.class.php on line 47

This does not occur on 2.5 and previous because it follows some recent changes in 2.6 which removed some automatic file inclusion