} else if (eCSSUnit_Image == mUnit) { mValue.mImage->Release();
  void  Reset()  // sets to null  {    if ((eCSSUnit_String <= mUnit) && (mUnit <= eCSSUnit_Counters) &&        (nsnull != mValue.mString)) {      nsCRT::free(mValue.mString);    } else if (eCSSUnit_URL == mUnit) {      mValue.mURL->Release();    }    mUnit = eCSSUnit_Null;    mValue.mInt = 0;  }