mBorderStyle[aSide] |= BORDER_COLOR_DEFINED;
  void SetBorderColor(PRUint8 aSide, nscolor aColor)   {    NS_ASSERTION(aSide <= NS_SIDE_LEFT, "bad side");     mBorderColor[aSide] = aColor;     mBorderStyle[aSide] &= ~BORDER_COLOR_SPECIAL;    mBorderStyle[aSide] |= BORDER_COLOR_DEFINED;   }