cleanup labnbook_supports()

lib.php

@@ -35,16 +35,15 @@ define('LABNBOOK_TABLE', 'labnbook');
  * @return true | null True if the feature is supported, null otherwise.
  */
 function labnbook_supports($feature) {
-    switch ($feature) {
-        case FEATURE_GRADE_HAS_GRADE:
-            return true;
-        case FEATURE_MOD_INTRO:
-            return true;
-        case FEATURE_BACKUP_MOODLE2:
-            return true;
-        default:
-            return null;
-    }
+    $features = [
+        //FEATURE_BACKUP_MOODLE2,
+        FEATURE_GRADE_HAS_GRADE,
+        //FEATURE_GRADE_OUTCOMES,
+        FEATURE_GROUPS,
+        FEATURE_MOD_INTRO,
+        FEATURE_SHOW_DESCRIPTION,
+    ];
+    return in_array($feature, $features) ? true : null;
 }
 
 /**
@@ -201,7 +200,7 @@ function labnbook_grade_item_delete($moduleinstance) {
  * @param int $userid Update grade of specific user only, 0 means all participants.
  */
 function labnbook_update_grades($moduleinstance, $userid = 0) {
-    global $CFG, $DB;
+    global $CFG;
     require_once($CFG->libdir.'/gradelib.php');
 
     // Populate array of grade objects indexed by userid.