ES6 symbols: Implement Symbol intrinsic and basic functionality

src/v8natives.js

Index: src/v8natives.js
diff --git a/src/v8natives.js b/src/v8natives.js
index 3978e88685156e69ec1660f1ea76d2f8b845b3b9..2a9302b1c5ececd320e6071232c2fdcbab07a1dd 100644
--- a/src/v8natives.js
+++ b/src/v8natives.js
@@ -231,10 +231,9 @@ $Object.prototype.constructor = $Object;
 
 // ECMA-262 - 15.2.4.2
 function ObjectToString() {
-  if (IS_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
-    return '[object Undefined]';
-  }
-  if (IS_NULL(this)) return '[object Null]';
+  if (IS_UNDEFINED(this) && !IS_UNDETECTABLE(this)) return "[object Undefined]";
+  if (IS_NULL(this)) return "[object Null]";
+  if (IS_SYMBOL(this)) return "[object Symbol]";
   return "[object " + %_ClassOf(ToObject(this)) + "]";
 }