Native context: do not put public symbols and flags on the js builtins object.

src/arraybuffer.js

 // Copyright 2013 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.
 
 (function(global, utils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
 
 var GlobalArrayBuffer = global.ArrayBuffer;
 var GlobalObject = global.Object;
 var MathMax;
 var MathMin;
 var ToNumber;
+var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
 
 utils.Import(function(from) {
   MathMax = from.MathMax;
   MathMin = from.MathMin;
   ToNumber = from.ToNumber;
 });
 
 // -------------------------------------------------------------------
 
 function ArrayBufferConstructor(length) { // length = 1
@@ skipping 57 matching lines @@
 
 // Set up the ArrayBuffer constructor function.
 %SetCode(GlobalArrayBuffer, ArrayBufferConstructor);
 %FunctionSetPrototype(GlobalArrayBuffer, new GlobalObject());
 
 // Set up the constructor property on the ArrayBuffer prototype object.
 %AddNamedProperty(
     GlobalArrayBuffer.prototype, "constructor", GlobalArrayBuffer, DONT_ENUM);
 
 %AddNamedProperty(GlobalArrayBuffer.prototype,
-    symbolToStringTag, "ArrayBuffer", DONT_ENUM | READ_ONLY);
+    toStringTagSymbol, "ArrayBuffer", DONT_ENUM | READ_ONLY);
 
-utils.InstallGetter(GlobalArrayBuffer.prototype, "byteLength", ArrayBufferGetByteLen);
+utils.InstallGetter(GlobalArrayBuffer.prototype, "byteLength",
+                    ArrayBufferGetByteLen);
 
 utils.InstallFunctions(GlobalArrayBuffer, DONT_ENUM, [
   "isView", ArrayBufferIsViewJS
 ]);
 
 utils.InstallFunctions(GlobalArrayBuffer.prototype, DONT_ENUM, [
   "slice", ArrayBufferSlice
 ]);
 
 })