class ActionController::Renderer

def normalize_keys(defaults, env)
  new_env = {}
  env.each_pair { |k, v| new_env[rack_key_for(k)] = rack_value_for(k, v) }
  defaults.each_pair do |k, v|
    key = rack_key_for(k)
    new_env[key] = rack_value_for(k, v) unless new_env.key?(key)
  end
  new_env["rack.url_scheme"] = new_env["HTTPS"] == "on" ? "https" : "http"
  new_env
end