mIsDone = PR_FALSE; if (mLast == mCurNode) return NS_OK; mCurNode = mLast; return NS_OK;
return PositionAt(mLast);
nsresult nsContentIterator::Last(){  if (!mLast)     return NS_ERROR_FAILURE;  mIsDone = PR_FALSE;  if (mLast == mCurNode)     return NS_OK;  mCurNode = mLast;  return NS_OK;}