MDL-41446 Completion: Incorrectly marks complete when grade data pres…

…ent with no actual grade

lib/completionlib.php

@@ -1277,9 +1277,12 @@ public function inform_grade_changed($cm, $item, $grade, $deleted) {
      * @return int Completion state e.g. COMPLETION_INCOMPLETE
      */
     public static function internal_get_grade_state($item, $grade) {
-        if (!$grade) {
+        // If no grade is supplied or the grade doesn't have an actual value, then
+        // this is not complete.
+        if (!$grade || (is_null($grade->finalgrade) && is_null($grade->rawgrade))) {
             return COMPLETION_INCOMPLETE;
         }
+
         // Conditions to show pass/fail:
         // a) Grade has pass mark (default is 0.00000 which is boolean true so be careful)
         // b) Grade is visible (neither hidden nor hidden-until)