Use Node.*_NODE instead of defining constants

[zpao]

I think this should be safe, cross browser at this point, but we should make sure. We shouldn't ever be running this code path server side, so I don't think we have to worry about that

// this
aNode.nodeType === Node.ELEMENT_NODE;

// instead of
var ELEMENT_NODE_TYPE = 1;
aNode.nodeType === ELEMENT_NODE_TYPE;

[syranide]

IE8 does not approve of this :)

[sophiebits]

Not sure I really see the motivation. Our current solution compresses better. :)

[zpao]

fiiiiiiiiine