[whatwg] getValues on PropertyNodeList is now redundant

[Ojan Vafai]

http://www.whatwg.org/specs/web-apps/current-work/multipage/common-dom-interfaces.html#propertynodelist

DOM4 now has NodeList inherit from Array (see
http://dvcs.w3.org/hg/domcore/raw-file/tip/Overview.html#interface-nodelist).
As such, the getValues function is no longer useful. PropertyNodeList
should just be a regular NodeList.

Ojan