hook_rest_server_execute_errors_alter doesn't actually have any values set for the $controller and $arguments parameters

The hook created on line 731 with the following call:

drupal_alter('rest_server_execute_errors', $error_alter_array, $controller, $arguments);

will never have any values set for $controller and $arguments because those variables do not exist within the handleException method on the RestServer object.

A potentential solution is to add two protected properties to the RESTServer object, set those properties to the values of the $controller and $argument in the error handling routine located in the last few lines of the RESTServer::handle method as follows:

    try {
      $result = services_controller_execute($controller, $arguments, $options);
    }
    catch (ServicesException $e) {
      $this->controller = $controller;
      $this->arguments = $arguments;
      $result = $this->handleException($e);
    }

and pass those properties as the third and fourth paramaters to the drupal_alter call as follows:

drupal_alter('rest_server_execute_errors', $error_alter_array, $this->controller, $this->arguments);