Event "question_manually_graded" is triggered in single comment view only

Event \mod_quiz\event\question_manually_graded is meant to provide a hook for plugins to react to manual grading (eg. by sending a comment/grade notification to the graded student(s)). However, in the current implementation, the event only gets triggered when the grade is set via /mod/quiz/comment.php. Grade and comment modifications in the "Quiz administration > Results > Manual grading" view (/mod/quiz/report.php?id=<id>&mode=grading (which is most likely the way most teachers grade their essay questions) don't seem to trigger the event.

Steps to reproduce

Grep for "question_manually_graded" in $CFG->dirroot.

Solution

Trigger the event for each quba at the end of quiz_grading_report::process_submitted_data() in /mod/quiz/report/grading/report.php after all attempt data has been committed (so that observers can access the new grading data).