mCombinedArea.SetRect(0,0,0,0);
  LineData(nsIFrame* aFrame, PRInt32 aCount, PRUint16 flags) {    mFirstChild = aFrame;    mChildCount = aCount;    mState = LINE_IS_DIRTY | LINE_NEED_DID_REFLOW | flags;    mFloaters = nsnull;    mNext = nsnull;    mBounds.SetRect(0,0,0,0);    mCarriedOutTopMargin = 0;    mCarriedOutBottomMargin = 0;  }