Merge pull request #1599 from fredj/1525

Trigger a render when a control is added to the map

src/ol/control/control.js

@@ -102,5 +102,6 @@ ol.control.Control.prototype.setMap = function(map) {
       this.listenerKeys.push(goog.events.listen(map,
           ol.MapEventType.POSTRENDER, this.handleMapPostrender, false, this));
     }
+    map.render();
   }
 };