logger warn has single argument

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

@@ -133,7 +133,7 @@ DataOverlay.prototype.setImagesDirectory = function (imagesDirectory) {
 
 DataOverlay.prototype.updateAlias = function (overlayAlias) {
   if (this.aliasById[overlayAlias.getId()] === undefined) {
-    logger.warn("Cannot update alias, it doesn't exist. Alias: ", overlayAlias.getId());
+    logger.warn("Cannot update alias, it doesn't exist. Alias: "+ overlayAlias.getId());
   } else {
     this.aliasById[overlayAlias.getId()].update(overlayAlias);
   }