additional test for getOverlay by id

frontend-js/src/test/js/ServerConnector-test.js

@@ -136,5 +136,13 @@ describe('ServerConnector', function() {
       assert.ok(url);
     });
   });
+  
+  it('getOverlayById', function() {
+    return ServerConnector.getOverlayById(90, "sample").then(function(overlay) {
+      assert.ok(overlay);
+    });
+  });
+  
+  
 
 });