nsresult  rv;
nsresult rv = NS_OK;
ViewportFrame::SetInitialChildList(nsIPresContext* aPresContext,                                   nsIAtom*        aListName,                                   nsIFrame*       aChildList){  nsresult  rv;  // See which child list to add the frames to#ifdef NS_DEBUG  nsFrame::VerifyDirtyBitSet(aChildList);#endif  if (nsLayoutAtoms::fixedList == aListName) {    mFixedFrames.SetFrames(aChildList);    rv = NS_OK;  } else {    rv = nsContainerFrame::SetInitialChildList(aPresContext, aListName, aChildList);  }  return rv;}