final MapWidget map = new MapWidget(atlanta, 13);
map.setSize("300px", "300px");
RootPanel.get().add(map);
final Marker marker = new Marker(atlanta);
map.addOverlay(marker);
marker.addMarkerInfoWindowBeforeCloseHandler(new MarkerInfoWindowBeforeCloseHandler() {
public void onInfoWindowBeforeClose(
MarkerInfoWindowBeforeCloseEvent event) {
assertEquals(event.getSender(), marker);
finishTest();