if (
        (SF_ENVIRONMENT == 'dev') &&
        (
          $this->getContext()->getRequest()->isXmlHttpRequest() ||
          strpos($response->getContentType(), 'html') === false ||
          $response->getStatusCode() == 304 ||
          $controller->getRenderMode() != sfView::RENDER_CLIENT ||
          $response->isHeaderOnly()
        )
      )
      {