public static ReadOnlyHttp2Headers trailers(boolean validateHeaders, AsciiString... otherHeaders) {
        return new ReadOnlyHttp2Headers(validateHeaders, EMPTY_ASCII_STRINGS, otherHeaders);
    }
@Test
    public void nullValuesAreNotAllowed() {
        assertThrows(IllegalArgumentException.class, new Executable() {
            @Override
            public void execute() {
                ReadOnlyHttp2Headers.trailers(true, new AsciiString("foo"), null);
            }
        });
    }