@Override
    protected boolean betterPostponeFlushNow() {
      //RC: Basically, we're trying to flush 'if idle': i.e., we don't want to
      //    issue a flush if somebody actively writes to indexes because flush
      //    will slow them down, if not stall them -- and (regular) flush is
      //    less important than e.g., a current UI task.
      //    So we issue a flush only if there _were no updates_ in indexes
      //    since the last invocation of this method:
      final int currentModCount = myLocalModCount.get();
      if (lastModCount != currentModCount) {
        lastModCount = currentModCount;
        return true;
      }
      return false;
    }
@Override
    protected boolean betterPostponeFlushNow()