Fixes bug when the student can see the exercise results see BT#5168 In case data_tracking is empty load the question list from the exercise this case should be really rare, Normally data_tracking should be ALWAYS registered.

main/exercice/exercise.lib.php

@@ -2046,8 +2046,15 @@ function display_question_list_by_attempt($objExercise, $exe_id, $save_user_resu
     //Getting attempt info
     $exercise_stat_info = $objExercise->get_stat_track_exercise_info_by_exe_id($exe_id);
     $question_list = array();
+    
     if (!empty($exercise_stat_info['data_tracking'])) {
         $question_list		= explode(',', $exercise_stat_info['data_tracking']);
+    } else {        
+        //Try getting the question list only if save result is off
+        if ($save_user_result == false) {
+            $question_list = $objExercise->get_validated_question_list();
+        }
+        error_log("Data tracking is empty! exe_id: $exe_id");
     }
     
     $counter = 1;