Reintroduce %GetRootNaN to fix MIPS.

src/runtime.js

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This files contains runtime support implemented in JavaScript.
 
 // CAUTION: Some of the functions specified in this file are called
 // directly from compiled code. These are the functions with names in
 // ALL CAPS. The compiled code passes the first argument in 'this'.
 
 
 /* -----------------------------------
    - - -   C o m p a r i s o n   - - -
    -----------------------------------
 */
 
 // The following declarations are shared with other native JS files.
 // They are all declared at this one spot to avoid redeclaration errors.
 var $Object = global.Object;
 var $Array = global.Array;
 var $String = global.String;
 var $Number = global.Number;
 var $Function = global.Function;
 var $Boolean = global.Boolean;
+var $NaN = %GetRootNaN();
 
 // ECMA-262 Section 11.9.3.
 function EQUALS(y) {
   if (IS_STRING(this) && IS_STRING(y)) return %StringEquals(this, y);
   var x = this;
 
   while (true) {
     if (IS_NUMBER(x)) {
       while (true) {
         if (IS_NUMBER(y)) return %NumberEquals(x, y);
@@ skipping 742 matching lines @@
 
 /* -----------------------------------------------
    - - -   J a v a S c r i p t   S t u b s   - - -
    -----------------------------------------------
 */
 
 function STRING_LENGTH_STUB(name) {
   var receiver = this;  // implicit first parameter
   return %_StringGetLength(%_JSValueGetValue(receiver));
 }