.buildOrThrow();
    ImmutableSet<String> uppercaseAcronyms =
        ImmutableSet.of(
            "CH", "ID", "DNT", "DNS", "DPR", "ECT", "GPC", "HTTP2", "IP", "MD5", "P3P", "RTT", "TE",
            "UA", "UID", "URL", "WWW", "XSS");

    for (Field field : httpHeadersFields()) {
      assertEquals(

   * header field name.
   *
   * @since 27.1
   */
  public static final String ORIGIN_TRIAL = "Origin-Trial";

  /** The HTTP {@code P3P} header field name. Limited browser support. */
  public static final String P3P = "P3P";

  /** The HTTP {@code Proxy-Authenticate} header field name. */
  public static final String PROXY_AUTHENTICATE = "Proxy-Authenticate";