Rename IS_SPEC_OBJECT macro to IS_RECEIVER.

src/js/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.
 
 (function(global, utils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
@@ skipping 28 matching lines @@
   return iterator;
 }
 
 
 // ES6 section 21.1.5.2.1 %StringIteratorPrototype%.next ( )
 function StringIteratorNext() {
   var iterator = this;
   var value = UNDEFINED;
   var done = true;
 
-  if (!IS_SPEC_OBJECT(iterator) ||
+  if (!IS_RECEIVER(iterator) ||
       !HAS_DEFINED_PRIVATE(iterator, stringIteratorNextIndexSymbol)) {
     throw MakeTypeError(kIncompatibleMethodReceiver,
                         'String Iterator.prototype.next');
   }
 
   var s = GET_PRIVATE(iterator, stringIteratorIteratedStringSymbol);
   if (!IS_UNDEFINED(s)) {
     var position = GET_PRIVATE(iterator, stringIteratorNextIndexSymbol);
     var length = TO_UINT32(s.length);
     if (position >= length) {
@@ skipping 33 matching lines @@
   'next', StringIteratorNext
 ]);
 %AddNamedProperty(StringIterator.prototype, toStringTagSymbol,
                   "String Iterator", READ_ONLY | DONT_ENUM);
 
 utils.SetFunctionName(StringPrototypeIterator, iteratorSymbol);
 %AddNamedProperty(GlobalString.prototype, iteratorSymbol,
                   StringPrototypeIterator, DONT_ENUM);
 
 })