code: public static Object registerInstance(BreakIterator iter, Locale locale, int kind) {
          return registerInstance(iter, ULocale.forLocale(locale), kind);
      }
docs: <strong>[icu]</strong> Registers a new break iterator of the indicated kind, to use in the given
  locale.  Clones of the iterator will be returned if a request for a break iterator
  of the given kind matches or falls back to this locale.
  
  <p>Because ICU may choose to cache BreakIterator objects internally, this must
  be called at application startup, prior to any calls to
  BreakIterator.getInstance to avoid undefined behavior.
  
  @param iter the BreakIterator instance to adopt.
  @param locale the Locale for which this instance is to be registered
  @param kind the type of iterator for which this instance is to be registered
  @return a registry key that can be used to unregister this instance
  @hide unsupported on Android