class ActionDispatch::Cookies

def call(env)
  request = ActionDispatch::Request.new env
  status, headers, body = @app.call(env)
  if request.have_cookie_jar?
    cookie_jar = request.cookie_jar
    unless cookie_jar.committed?
      cookie_jar.write(headers)
      if headers[HTTP_HEADER].respond_to?(:join)
        headers[HTTP_HEADER] = headers[HTTP_HEADER].join("\n")
      end
    end
  end
  [status, headers, body]
end