code: @Override
      public TimeZone cloneAsThawed() {
          OlsonTimeZone tz = (OlsonTimeZone)super.cloneAsThawed();
          if (finalZone != null) {
              // TODO Do we really need this?
              finalZone.setID(getID());
              tz.finalZone = (SimpleTimeZone) finalZone.clone();
          }
  
          // Following data are read-only and never changed.
          // Therefore, shallow copies should be sufficient.
          //
          // transitionTimes64
          // typeMapData
          // typeOffsets
  
          tz.isFrozen = false;
          return tz;
      }
docs: /* (non-Javadoc)
  @see android.icu.util.TimeZone#cloneAsThawed()