code: public boolean syncWaterMarks(String source, long lwmScn, long hwmScn) {
          setWaterMarks(source, lwmScn, hwmScn);
          return flush();
      }
docs: Sets and flushes the water marks of a source.
  
  @param source - the source
  @param lwmScn - the low water mark SCN
  @param hwmScn - the high water mark SCN
  @return <tt>true</tt> if flush is successful.