[es6] Introduce a dedicated JSIteratorResult type.

src/factory.h

 // 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.
 
 #ifndef V8_FACTORY_H_
 #define V8_FACTORY_H_
 
 #include "src/isolate.h"
 #include "src/messages.h"
 
@@ skipping 457 matching lines @@
   Handle<JSDataView> NewJSDataView(Handle<JSArrayBuffer> buffer,
                                    size_t byte_offset, size_t byte_length);
 
   Handle<JSMap> NewJSMap();
   Handle<JSSet> NewJSSet();
 
   // TODO(aandrey): Maybe these should take table, index and kind arguments.
   Handle<JSMapIterator> NewJSMapIterator();
   Handle<JSSetIterator> NewJSSetIterator();
 
+  // Creates a new JSIteratorResult object with the arguments {value} and
+  // {done}.  Implemented according to ES6 section 7.4.7 CreateIterResultObject.
+  Handle<JSIteratorResult> NewJSIteratorResult(Handle<Object> value,
+                                               Handle<Object> done);
+
   // Allocates a Harmony proxy.
   Handle<JSProxy> NewJSProxy(Handle<Object> handler, Handle<Object> prototype);
 
   // Allocates a Harmony function proxy.
   Handle<JSProxy> NewJSFunctionProxy(Handle<Object> handler,
                                      Handle<Object> call_trap,
                                      Handle<Object> construct_trap,
                                      Handle<Object> prototype);
 
   // Reinitialize an JSGlobalProxy based on a constructor.  The object
@@ skipping 229 matching lines @@
   // Reinitialize a JSProxy into an (empty) JS object of respective type and
   // size, but keeping the original prototype.  The receiver must have at least
   // the size of the new object.  The object is reinitialized and behaves as an
   // object that has been freshly allocated.
   void ReinitializeJSProxy(Handle<JSProxy> proxy, InstanceType type, int size);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_FACTORY_H_