* @return Content object, or 0 if no content was recognised in the XML.
*/
shared_ptr<Content>
-content_factory (shared_ptr<const Film> film, cxml::NodePtr node, int version, list<string>& notes)
+content_factory (shared_ptr<const Film> film, cxml::ConstNodePtr node, int version, list<string>& notes)
{
string const type = node->string_child ("Type");