Method register

github-actions/saucelabs/set-saucelabs-env.js:13070–13078

(dispatcher, key)

      webidl.converters.ResponseInit = webidl.dictionaryConverter([
        {
          key: "status",
          converter: webidl.converters["unsigned short"],
          defaultValue: () => 200
        },
        {
          key: "statusText",
          converter: webidl.converters.ByteString,
          defaultValue: () => ""
        },
        {
          key: "headers",
          converter: webidl.converters.HeadersInit