Add remaining @@toStringTag symbols to builtins

src/collection-iterator.js

 // Copyright 2014 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.
 
 'use strict';
 
 
 // This file relies on the fact that the following declaration has been made
 // in runtime.js:
 // var $Set = global.Set;
@@ skipping 59 matching lines @@
   %SetCode(SetIterator, SetIteratorConstructor);
   %FunctionSetPrototype(SetIterator, new $Object());
   %FunctionSetInstanceClassName(SetIterator, 'Set Iterator');
   InstallFunctions(SetIterator.prototype, DONT_ENUM, $Array(
     'next', SetIteratorNextJS
   ));
 
   %FunctionSetName(SetIteratorSymbolIterator, '[Symbol.iterator]');
   %AddNamedProperty(SetIterator.prototype, symbolIterator,
       SetIteratorSymbolIterator, DONT_ENUM);
+  %AddNamedProperty(SetIterator.prototype, symbolToStringTag,
+      "Set Iterator", READ_ONLY | DONT_ENUM);
 }
 
 SetUpSetIterator();
 
 
 function ExtendSetPrototype() {
   %CheckIsBootstrapping();
 
   InstallFunctions($Set.prototype, DONT_ENUM, $Array(
     'entries', SetEntries,
@@ skipping 77 matching lines @@
   %SetCode(MapIterator, MapIteratorConstructor);
   %FunctionSetPrototype(MapIterator, new $Object());
   %FunctionSetInstanceClassName(MapIterator, 'Map Iterator');
   InstallFunctions(MapIterator.prototype, DONT_ENUM, $Array(
     'next', MapIteratorNextJS
   ));
 
   %FunctionSetName(MapIteratorSymbolIterator, '[Symbol.iterator]');
   %AddNamedProperty(MapIterator.prototype, symbolIterator,
       MapIteratorSymbolIterator, DONT_ENUM);
+  %AddNamedProperty(MapIterator.prototype, symbolToStringTag,
+      "Map Iterator", READ_ONLY | DONT_ENUM);
 }
 
 SetUpMapIterator();
 
 
 function ExtendMapPrototype() {
   %CheckIsBootstrapping();
 
   InstallFunctions($Map.prototype, DONT_ENUM, $Array(
     'entries', MapEntries,
     'keys', MapKeys,
     'values', MapValues
   ));
 
   %AddNamedProperty($Map.prototype, symbolIterator, MapEntries, DONT_ENUM);
 }
 
 ExtendMapPrototype();