code: protected CLDR.Locale bundleMatch(CLDR.Locale locale) {
      locale = DEFAULT_CONTENT.getOrDefault(locale, locale);
      return bundleMatcher.match((MetaLocale)locale);
    }
docs: Locate the correct bundle identifier for the given resolved locale. Note that
  the bundle identifier is not terribly useful outside of the CLDR library, since
  it may in many cases carry incomplete information for the intended public locale.
  For example, the bundle used for "en-Latn-US" is "en" which is missing critical
  subtags and as such should not be used to identify the "en-Latn-US" locale.