Remove unnecessary void 0.

Author: savetheclocktower

src/prototype/dom/dom.js

@@ -1,6 +1,6 @@
 (function(GLOBAL) {
 
-  var UNDEFINED = void 0;
+  var UNDEFINED;
   var SLICE = Array.prototype.slice;
 
   // Try to reuse the same created element as much as possible. We'll use