if (NS_AUTOMARGIN == aOppositeMargin) { margin = (aContainBlockSize - aFrameSize) / 2; }
if (NS_AUTOMARGIN == aOppositeMargin) margin = nsTableFrame::RoundToPixel((aContainBlockSize - aFrameSize) / 2, aPixelToTwips);
nscoord CalcAutoMargin(nscoord aAutoMargin,                       nscoord aOppositeMargin,                       nscoord aContainBlockSize,                       nscoord aFrameSize){  nscoord margin;  if (NS_AUTOMARGIN == aOppositeMargin) {    margin = (aContainBlockSize - aFrameSize) / 2;  }  else {    margin = aContainBlockSize - aFrameSize - aOppositeMargin;  }  return PR_MAX(0, margin);}