class ActionDispatch::Cookies::CookieJar

def make_set_cookie_header(header)
  header = @set_cookies.inject(header) { |m, (k, v)|
    if write_cookie?(v)
      ::Rack::Utils.add_cookie_to_header(m, k, v)
    else
      m
    end
  }
  @delete_cookies.inject(header) { |m, (k, v)|
    ::Rack::Utils.add_remove_cookie_to_header(m, k, v)
  }
end