Add developer debugging to something that should not happen, and fix one instance of it.

lib/questionlib.php

@@ -1073,6 +1073,7 @@ function question_process_responses(&$question, &$state, $action, $cmoptions, &$
 
     // If $action->event is not set that implies saving
     if (! isset($action->event)) {
+        debugging('Ambiguous action in question_process_responses.' , DEBUG_DEVELOPER);
         $action->event = QUESTION_EVENTSAVE;
     }
     // If submitted then compare against last graded

mod/quiz/attempt.php

@@ -371,6 +371,7 @@
         foreach($questionidarray as $i) {
             if (!isset($actions[$i])) {
                 $actions[$i]->responses = array('' => '');
+                $actions[$i]->event = QUESTION_EVENTSAVE;
             }
             $actions[$i]->timestamp = $timestamp;
             question_process_responses($questions[$i], $states[$i], $actions[$i], $quiz, $attempt);