anchor.diff:      return completer.future;
     }
   
  -
  +  // TODO(ericarnold): Complete a future / stream.
     Future<ServiceActionEvent> sendAction(String serviceId, String actionId,
         String callId, [String data = ""]) {
  -    // TODO(ericarnold): Implement
       // TODO(ericarnold): implement callId response
  +    _sendPort.send(
  +        {"serviceId": serviceId, "actionId": actionId, "data": data});
     }
   
     void sendResponse(ServiceActionEvent event, String data) {
  
positive.code:  * Special service for handling Chrome app calls that the isolate
   * cannot handle on its own.
   */
  class ExampleService extends Service {
    String serviceId = "example";
  
    ExampleService(Services services, _IsolateHandler handler)
        : super(services, handler);
  }
  
  /**
  
negative.code:   // and invokes the Future once response has been received.
    Future<ServiceActionEvent> _sendAction(String actionId, [Map data]) {
      // TODO(ericarnold): Implement
      String callId = _getNewCallId();
  
      return _isolateHandler.onceIsolateReady.then((_){
        _isolateHandler.sendAction(serviceId, actionId, callId);
        return _isolateHandler.onIsolateResponse(callId).first;
      }).then((ActionEvent event){
        print("pong");
        return new Future.value("poong");
      });
    }
  }
  
  