normalize_keys

# File actionpack/lib/action_controller/renderer.rb, line 105
      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