the_attr_node_todo

!meta title="The Attr Node todo" !meta author="Struggleyb" !meta date="2009-08-22T13:35:45Z"

!toc

1. For bool property, we deal it as: if there is a Attr node for it, its value is true, otherwise its value is false;
2. All Attr node's value type are DOMString, there is no other types if the design now is correct;
3. Remove the include/dom/core/attr.h additional attribute's type code when making sure the design is correct.