new Error takes single string argument

frontend-js/src/main/js/map/data/MapModel.js

@@ -581,7 +581,7 @@ MapModel.prototype.isAvailable = function (ie, complete) {
     }
     element = this._pointsData[id];
   } else {
-    throw new Error("Unknown type: " + ie.getType(), complete);
+    throw new Error("Unknown type: " + ie.getType() + "," + complete);
   }
   if (element === undefined) {
     return false;