//wait
ReturnMessage returnMessage = Fiber.yield();
handler.getLog().debug("Got response from server");
//handle message
if (returnMessage.isException()) {
throw new JavaScriptException(handler.getJavaScriptObjectFromValue(
returnMessage.getReturnValue()));
} else {
return (T) handler.getJavaScriptObjectFromValue(
returnMessage.getReturnValue());
}