docs: public String getShortName(long instant, Locale locale) {
          if (locale == null) {
              locale = Locale.getDefault();
          }
          String nameKey = getNameKey(instant);
          if (nameKey == null) {
              return iID;
          }
          String name;
          NameProvider np = getNameProvider();
          if (np instanceof DefaultNameProvider) {
              name = ((DefaultNameProvider) np).getShortName(locale, iID, nameKey, isStandardOffset(instant));
          } else {
              name = np.getShortName(locale, iID, nameKey);
          }
          if (name != null) {
              return name;
          }
          return printOffset(getOffset(instant));
      }