PHRAS-3371 fix key navigation

lib/classes/record/preview.php

@@ -552,6 +552,14 @@ class record_preview extends record_adapter
         return $this->statistics;
     }
 
+    /**
+     * @return int
+     */
+    public function getTotal()
+    {
+        return isset($this->total) ? $this->total : 0;
+    }
+
     /**
      * @return media_adapter
      */