Cosmetic: Add macros for NaN, undefined and Infinity to native js code.

src/runtime.js

Index: src/runtime.js
diff --git a/src/runtime.js b/src/runtime.js
index 5339570ef6ee6d8e42430765caf828d7d4efa64e..ce11c37079e6a24b10b4a0fb5d44e76a8dd9ce08 100644
--- a/src/runtime.js
+++ b/src/runtime.js
@@ -526,8 +526,8 @@ function ToNumber(x) {
                                     : %StringToNumber(x);
   }
   if (IS_BOOLEAN(x)) return x ? 1 : 0;
-  if (IS_UNDEFINED(x)) return $NaN;
-  if (IS_SYMBOL(x)) return $NaN;
+  if (IS_UNDEFINED(x)) return NAN;
+  if (IS_SYMBOL(x)) return NAN;
   return (IS_NULL(x)) ? 0 : ToNumber(%DefaultNumber(x));
 }
 
@@ -537,8 +537,8 @@ function NonNumberToNumber(x) {
                                     : %StringToNumber(x);
   }
   if (IS_BOOLEAN(x)) return x ? 1 : 0;
-  if (IS_UNDEFINED(x)) return $NaN;
-  if (IS_SYMBOL(x)) return $NaN;
+  if (IS_UNDEFINED(x)) return NAN;
+  if (IS_SYMBOL(x)) return NAN;
   return (IS_NULL(x)) ? 0 : ToNumber(%DefaultNumber(x));
 }