nsBlockFrame::FirstChild(nsIAtom* aListName, nsIFrame** aFirstChild) const
nsBlockFrame::FirstChild(nsIFrame*& aFirstChild) const
nsBlockFrame::FirstChild(nsIAtom* aListName, nsIFrame** aFirstChild) const{  NS_PRECONDITION(nsnull != aFirstChild, "null OUT parameter pointer");  if (nsnull == aListName) {    *aFirstChild = (nsnull != mLines) ? mLines->mFirstChild : nsnull;    return NS_OK;  }  else if (aListName == nsLayoutAtoms::floaterList) {    *aFirstChild = mFloaters.FirstChild();    return NS_OK;  }  else if (aListName == nsLayoutAtoms::bulletList) {    if (HaveOutsideBullet()) {      *aFirstChild = mBullet;    }    else {      *aFirstChild = nsnull;    }    return NS_OK;  }  *aFirstChild = nsnull;  return NS_ERROR_INVALID_ARG;}