additional asserts added

frontend-js/src/test/js/map/Submap-test.js

 "use strict";
 
 var Helper = require('../Helper');
+var logger = require('../logger');
 
 var Submap = require('../../../main/js/map/Submap');
 var chai = require('chai');
@@ -19,5 +20,7 @@ describe('Submap', function() {
     
     var submap = new Submap(map, model);
     assert.ok(submap);
+    assert.equal(logger.getWarnings().length, 0);
+    assert.equal(logger.getErrors().length, 0);
   });
 });