code: private String buildLocaleUrl(String selectedLocale) {
  		UrlBuilder builder = Window.Location.createUrlBuilder();
  		builder.removeParameter("locale");
  		if (!"default".equals(selectedLocale)) {
  			builder.setParameter("locale", selectedLocale);
  		}
  		return builder.buildString();
  	}
docs: Build the correct URL for the new locale.