code: @Override
      public Symmetry010Date dateYearDay(Era era, int yearOfEra, int dayOfYear) {
          return dateYearDay(prolepticYear(era, yearOfEra), dayOfYear);
      }
docs: Obtains a local date in Symmetry010 calendar system from the
  era, year-of-era and day-of-year fields.
  
  @param era  the Symmetry010 era, not null
  @param yearOfEra  the year-of-era
  @param dayOfYear  the day-of-year
  @return the Symmetry010 local date, not null
  @throws DateTimeException if unable to create the date
  @throws ClassCastException if the {@code era} is not a {@code IsoEra}