reference to InvalidCredentialsError added

frontend-js/src/main/js/gui/LoginDialog.js

@@ -4,6 +4,7 @@
 
 var AbstractGuiElement = require('./AbstractGuiElement');
 var GuiConnector = require('../GuiConnector');
+var InvalidCredentialsError = require('../InvalidCredentialsError');
 var PanelControlElementType = require('./PanelControlElementType');
 
 var Functions = require('../functions');