ChildIterator(const ChildIterator& aOther) : mContent(aOther.mContent), mIndex(aOther.mIndex), mNodes(aOther.mNodes) {}
ChildIterator() : mIndex(0) {}
  ChildIterator(const ChildIterator& aOther)    : mContent(aOther.mContent),      mIndex(aOther.mIndex),      mNodes(aOther.mNodes) {}