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

src/messages.js

 // Copyright 2012 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 $errorToString;
 var MakeError;
 var MakeEvalError;
 var MakeRangeError;
 var MakeReferenceError;
 var MakeSyntaxError;
 var MakeTypeError;
 var MakeURIError;
 
 (function(global, utils) {
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
 
 var ArrayJoin;
 var Bool16x8ToString;
 var Bool32x4ToString;
 var Bool8x16ToString;
 var callSiteReceiverSymbol =
-    utils.GetPrivateSymbol("call_site_receiver_symbol");
+    utils.ImportNow("call_site_receiver_symbol");
 var callSiteFunctionSymbol =
-    utils.GetPrivateSymbol("call_site_function_symbol");
+    utils.ImportNow("call_site_function_symbol");
 var callSitePositionSymbol =
-    utils.GetPrivateSymbol("call_site_position_symbol");
-var callSiteStrictSymbol = utils.GetPrivateSymbol("call_site_strict_symbol");
+    utils.ImportNow("call_site_position_symbol");
+var callSiteStrictSymbol =
+    utils.ImportNow("call_site_strict_symbol");
 var Float32x4ToString;
 var formattedStackTraceSymbol =
-    utils.GetPrivateSymbol("formatted_stack_trace_symbol");
+    utils.ImportNow("formatted_stack_trace_symbol");
 var FunctionSourceString
 var GlobalObject = global.Object;
 var Int16x8ToString;
 var Int32x4ToString;
 var Int8x16ToString;
 var InternalArray = utils.InternalArray;
-var internalErrorSymbol = utils.GetPrivateSymbol("internal_error_symbol");
+var internalErrorSymbol = utils.ImportNow("internal_error_symbol");
 var ObjectDefineProperty;
 var ObjectToString;
-var stackTraceSymbol = utils.GetPrivateSymbol("stack_trace_symbol");
+var stackTraceSymbol = utils.ImportNow("stack_trace_symbol");
 var StringCharAt;
 var StringIndexOf;
 var StringSubstring;
-var ToString;
+var SymbolToString;
+var ToString = utils.ImportNow("ToString");
 var Uint16x8ToString;
 var Uint32x4ToString;
 var Uint8x16ToString;
 
 utils.Import(function(from) {
   ArrayJoin = from.ArrayJoin;
   Bool16x8ToString = from.Bool16x8ToString;
   Bool32x4ToString = from.Bool32x4ToString;
   Bool8x16ToString = from.Bool8x16ToString;
   Float32x4ToString = from.Float32x4ToString;
   FunctionSourceString = from.FunctionSourceString;
   Int16x8ToString = from.Int16x8ToString;
   Int32x4ToString = from.Int32x4ToString;
   Int8x16ToString = from.Int8x16ToString;
   ObjectDefineProperty = from.ObjectDefineProperty;
   ObjectToString = from.ObjectToString;
   StringCharAt = from.StringCharAt;
   StringIndexOf = from.StringIndexOf;
   StringSubstring = from.StringSubstring;
+  SymbolToString = from.SymbolToString;
   Uint16x8ToString = from.Uint16x8ToString;
   Uint32x4ToString = from.Uint32x4ToString;
   Uint8x16ToString = from.Uint8x16ToString;
 });
 
-utils.ImportNow(function(from) {
-  ToString = from.ToString;
-});
-
 // -------------------------------------------------------------------
 
 var GlobalError;
 var GlobalTypeError;
 var GlobalRangeError;
 var GlobalURIError;
 var GlobalSyntaxError;
 var GlobalReferenceError;
 var GlobalEvalError;
 
@@ skipping 12 matching lines @@
   if (IS_UNDEFINED(obj)) return 'undefined';
   if (IS_NULL(obj)) return 'null';
   if (IS_FUNCTION(obj)) {
     var str = %_CallFunction(obj, obj, FunctionSourceString);
     if (str.length > 128) {
       str = %_SubString(str, 0, 111) + "...<omitted>..." +
             %_SubString(str, str.length - 2, str.length);
     }
     return str;
   }
-  if (IS_SYMBOL(obj)) return %_CallFunction(obj, $symbolToString);
+  if (IS_SYMBOL(obj)) return %_CallFunction(obj, SymbolToString);
   if (IS_SIMD_VALUE(obj)) {
     switch (typeof(obj)) {
       case 'float32x4': return %_CallFunction(obj, Float32x4ToString);
       case 'int32x4':   return %_CallFunction(obj, Int32x4ToString);
       case 'int16x8':   return %_CallFunction(obj, Int16x8ToString);
       case 'int8x16':   return %_CallFunction(obj, Int8x16ToString);
       case 'uint32x4':   return %_CallFunction(obj, Uint32x4ToString);
       case 'uint16x8':   return %_CallFunction(obj, Uint16x8ToString);
       case 'uint8x16':   return %_CallFunction(obj, Uint8x16ToString);
       case 'bool32x4':  return %_CallFunction(obj, Bool32x4ToString);
@@ skipping 917 matching lines @@
   "range_error_function", GlobalRangeError,
   "reference_error_function", GlobalReferenceError,
   "stack_overflow_boilerplate", StackOverflowBoilerplate,
   "syntax_error_function", GlobalSyntaxError,
   "to_detail_string_fun", ToDetailString,
   "type_error_function", GlobalTypeError,
   "uri_error_function", GlobalURIError,
 ]);
 
 });