Bugs in several modules when accessing groups in recent activity report

While working on MDL-34397 I was reviewing all cases of writing to course_modinfo objects (returned by get_fast_modinfo()). I found copy-pasted code for accessing module groups in following files:

• course/recent.php
• mod/assign/lib.php
• mod/assignment/lib.php
• mod/chat/lib.php
• mod/feedback/lib.php
• mod/forum/lib.php
• mod/quiz/lib.php
• mod/wiki/lib.php
• mod/workshop/lib.php

Of which assign, assignment, feedback, quiz and workshop access the $modinfo->groups incorrectly - this array is indexed by groupping id but acceed with module id as a key instead.

Also mod_glossary accesses groups incorrectly

Will try to understand the error it can cause and create tests.

Creating separate issue for it because it may need fixing in stable versions too.