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

src/date.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.
 
 var $createDate;
 
 // -------------------------------------------------------------------
 
 (function(global, utils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
 
 var GlobalDate = global.Date;
 var InternalArray = utils.InternalArray;
 var IsFinite;
 var MathAbs;
 var MathFloor;
 var ToNumber;
+var toPrimitiveSymbol = utils.ImportNow("to_primitive_symbol");
 var ToString;
 
 utils.Import(function(from) {
   IsFinite = from.IsFinite;
   MathAbs = from.MathAbs;
   MathFloor = from.MathFloor;
   ToNumber = from.ToNumber;
   ToString = from.ToString;
 });
 
@@ skipping 806 matching lines @@
 
 // Set up non-enumerable properties of the Date object itself.
 utils.InstallFunctions(GlobalDate, DONT_ENUM, [
   "UTC", DateUTC,
   "parse", DateParse,
   "now", DateNow
 ]);
 
 // Set up non-enumerable constructor property of the Date prototype object.
 %AddNamedProperty(GlobalDate.prototype, "constructor", GlobalDate, DONT_ENUM);
-utils.SetFunctionName(DateToPrimitive, symbolToPrimitive);
-%AddNamedProperty(GlobalDate.prototype, symbolToPrimitive, DateToPrimitive,
+utils.SetFunctionName(DateToPrimitive, toPrimitiveSymbol);
+%AddNamedProperty(GlobalDate.prototype, toPrimitiveSymbol, DateToPrimitive,
                   DONT_ENUM | READ_ONLY);
 
 // Set up non-enumerable functions of the Date prototype object and
 // set their names.
 utils.InstallFunctions(GlobalDate.prototype, DONT_ENUM, [
   "toString", DateToString,
   "toDateString", DateToDateString,
   "toTimeString", DateToTimeString,
   "toLocaleString", DateToLocaleString,
   "toLocaleDateString", DateToLocaleDateString,
@@ skipping 36 matching lines @@
   "toUTCString", DateToUTCString,
   "getYear", DateGetYear,
   "setYear", DateSetYear,
   "toISOString", DateToISOString,
   "toJSON", DateToJSON
 ]);
 
 %InstallToContext(["create_date_fun", CreateDate]);
 
 })