void MutationObserverRegistration::addRegistrationNodesToSet(HashSet<Node*>& nodes) const
{
    nodes.add(m_registrationNode);
    if (!m_transientRegistrationNodes)
        return;
    for (NodeHashSet::const_iterator iter = m_transientRegistrationNodes->begin(); iter != m_transientRegistrationNodes->end(); ++iter)
        nodes.add(iter->get());
}
void MutationObserverRegistration::addRegistrationNodesToSet(WillBeHeapHashSet<RawPtrWillBeMember<Node>>& nodes) const
{
    ASSERT(m_registrationNode);
    nodes.add(m_registrationNode.get());
    if (!m_transientRegistrationNodes)
        return;
    for (NodeHashSet::const_iterator iter = m_transientRegistrationNodes->begin(); iter != m_transientRegistrationNodes->end(); ++iter)
        nodes.add(iter->get());
}