Chrome.getExtension().getOnConnectExternalEvent().addListener(
new ConnectExternalEvent.Listener() {
public void onConnectExternal(Port port) {
if (portName.equals(port.getName())) {
// Provision a DataInstance and a TabDescription.
DataInstance dataInstance = ExternalExtensionDataInstance.create(port);
TabDescription tabDescription = TabDescription.create(
tabId, connectRequest.getTitle(),
connectRequest.getUrl());
// Now remember the DataInstance and TabDescription, and