assertEquals(Integer.valueOf(3), map.remove("two"));
    assertThat(strings).containsExactly("one", "three").inOrder();
    assertEquals(mapEntry("three", 5), map.subMap("one", false, "zzz", true).pollLastEntry());
    assertThat(strings).contains("one");
  }

  @GwtIncompatible // NavigableMap
  public void testAsMapNavigableSubViewKeySetsDoNotSupportAdd() {

    /** RFC 1123 date formatter */
    private static final DateTimeFormatter RFC_1123_FORMATTER =
            DateTimeFormatter.ofPattern("EEE, dd MMM yyyy HH:mm:ss zzz", Locale.ENGLISH).withZone(ZoneId.of("GMT"));

    /**
     * Parses the last modified date from a string value.
     * Supports RFC 1123, RFC 1036, and ANSI C date formats.