[dom] Setting input value to null results in node.value === “null" in IE9

[thekeyboardbum]

<input id="testnode" value=""/>
YUI().use('node',function(Y) {
    Y.one('#testnode').set('value',null); 
});

(12:07:23 PM) Tew: (it would probably not even occur to me to set empty input with null instead of an empty string)
(12:09:13 PM) apipkin: Tew: i agree. it’s a little strange to stringify the value from null to ”null” though
(12:15:29 PM) apipkin: Soooo, if that’s the case in IE9+ YUI should probably adjust for that within dom-attrs https://github.com/yui/yui3/blob/master/src/dom/js/dom-attrs.js#L128

ping @msweeney

[okuryu]

#1611 has been merged.