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

src/harmony-atomics.js

 // Copyright 2015 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 GlobalObject = global.Object;
 var MathMax;
 var ToNumber;
+var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
 
 utils.Import(function(from) {
   MathMax = from.MathMax;
   ToNumber = from.ToNumber;
 });
 
 // -------------------------------------------------------------------
 
 
 function CheckSharedTypedArray(sta) {
@@ skipping 158 matching lines @@
 // -------------------------------------------------------------------
 
 function AtomicsConstructor() {}
 
 var Atomics = new AtomicsConstructor();
 
 %InternalSetPrototype(Atomics, GlobalObject.prototype);
 %AddNamedProperty(global, "Atomics", Atomics, DONT_ENUM);
 %FunctionSetInstanceClassName(AtomicsConstructor, 'Atomics');
 
-%AddNamedProperty(Atomics, symbolToStringTag, "Atomics", READ_ONLY | DONT_ENUM);
+%AddNamedProperty(Atomics, toStringTagSymbol, "Atomics", READ_ONLY | DONT_ENUM);
 
 // These must match the values in src/futex-emulation.h
 utils.InstallConstants(Atomics, [
   "OK", 0,
   "NOTEQUAL", -1,
   "TIMEDOUT", -2,
 ]);
 
 utils.InstallFunctions(Atomics, DONT_ENUM, [
   "compareExchange", AtomicsCompareExchangeJS,
   "load", AtomicsLoadJS,
   "store", AtomicsStoreJS,
   "add", AtomicsAddJS,
   "sub", AtomicsSubJS,
   "and", AtomicsAndJS,
   "or", AtomicsOrJS,
   "xor", AtomicsXorJS,
   "exchange", AtomicsExchangeJS,
   "isLockFree", AtomicsIsLockFreeJS,
   "futexWait", AtomicsFutexWaitJS,
   "futexWake", AtomicsFutexWakeJS,
   "futexWakeOrRequeue", AtomicsFutexWakeOrRequeueJS,
 ]);
 
 })