Make all global private symbols own symbols.

src/string-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 $String = global.String;
@@ skipping 20 matching lines @@
 // 21.1.5.2.2 %StringIteratorPrototype%[@@iterator]
 function StringIteratorIterator() {
   return this;
 }
 
 
 // 21.1.5.2.1 %StringIteratorPrototype%.next( )
 function StringIteratorNext() {
   var iterator = ToObject(this);
 
-  if (!HAS_PRIVATE(iterator, stringIteratorIteratedStringSymbol)) {
+  if (!HAS_DEFINED_PRIVATE(iterator, stringIteratorNextIndexSymbol)) {
     throw MakeTypeError('incompatible_method_receiver',
                         ['String Iterator.prototype.next']);
   }
 
   var s = GET_PRIVATE(iterator, stringIteratorIteratedStringSymbol);
   if (IS_UNDEFINED(s)) {
     return CreateIteratorResultObject(UNDEFINED, true);
   }
 
   var position = GET_PRIVATE(iterator, stringIteratorNextIndexSymbol);
   var length = TO_UINT32(s.length);
 
   if (position >= length) {
-    SET_PRIVATE(iterator, stringIteratorIteratedStringSymbol, UNDEFINED);
+    SET_PRIVATE(iterator, stringIteratorIteratedStringSymbol,
+                UNDEFINED);
     return CreateIteratorResultObject(UNDEFINED, true);
   }
 
   var first = %_StringCharCodeAt(s, position);
   var resultString = %_StringCharFromCode(first);
   position++;
 
   if (first >= 0xD800 && first <= 0xDBFF && position < length) {
     var second = %_StringCharCodeAt(s, position);
     if (second >= 0xDC00 && second <= 0xDFFF) {
@@ skipping 31 matching lines @@
 
 
 function ExtendStringPrototypeWithIterator() {
   %CheckIsBootstrapping();
 
   %FunctionSetName(StringPrototypeIterator, '[Symbol.iterator]');
   %AddNamedProperty($String.prototype, symbolIterator,
                     StringPrototypeIterator, DONT_ENUM);
 }
 ExtendStringPrototypeWithIterator();