compare(other) {
    if (this.high_ == other.high_) {
      if (this.low_ == other.low_) {
        return 0;
      }
      return this.getLowBitsUnsigned() > other.getLowBitsUnsigned() ? 1 : -1;
    }
    return this.high_ > other.high_ ? 1 : -1;
  }
Compares this Long with the given one.
@param {?Long} other Long to compare against.
@return {number} 0 if they are the same, 1 if the this is greater, and -1
    if the given one is greater.