nsresult nsContentIterator::Init(nsIContent* aRoot)
nsresult nsGeneratedContentIterator::Init(nsIFocusTracker *aTracker, nsIDOMRange* aRange, PRBool aSelectBefore, PRBool aSelectAfter)
nsresult nsContentIterator::Init(nsIContent* aRoot){  if (!aRoot)     return NS_ERROR_NULL_POINTER;   mIsDone = PR_FALSE;  nsCOMPtr<nsIContent> root( do_QueryInterface(aRoot) );  mFirst = GetDeepFirstChild(root);   mLast = root;  mCommonParent = root;  mCurNode = mFirst;  return NS_OK;}