package ol;

/**
 * 
 * @author Tino Desjardins
 *
 */
public class GwtOL3BaseTestCase extends BaseTestCase {

    public GwtOL3BaseTestCase() {
        super("http://openlayers.org/en/v3.12.1/build/ol.js", "GwtOL3Test", 10000);
    }
    
}

package ol;

/**
 *
 * @author Tino Desjardins
 *
 */
public class GwtOL3BaseTestCase extends BaseTestCase {

    public GwtOL3BaseTestCase() {
        super("http://openlayers.org/en/v3.13.0/build/ol.js", "GwtOL3Test", 10000);
    }

}

Switch from OL v3.12.1 to OL v3.13.0