[runtime] We don't need an actual instance type for JSIteratorResult.

src/objects-inl.h

 // 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.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 692 matching lines @@
 bool Object::IsJSProxy() const {
   if (!Object::IsHeapObject()) return false;
   return  HeapObject::cast(this)->map()->IsJSProxyMap();
 }
 
 
 TYPE_CHECKER(JSSet, JS_SET_TYPE)
 TYPE_CHECKER(JSMap, JS_MAP_TYPE)
 TYPE_CHECKER(JSSetIterator, JS_SET_ITERATOR_TYPE)
 TYPE_CHECKER(JSMapIterator, JS_MAP_ITERATOR_TYPE)
-TYPE_CHECKER(JSIteratorResult, JS_ITERATOR_RESULT_TYPE)
 TYPE_CHECKER(JSWeakMap, JS_WEAK_MAP_TYPE)
 TYPE_CHECKER(JSWeakSet, JS_WEAK_SET_TYPE)
 TYPE_CHECKER(JSContextExtensionObject, JS_CONTEXT_EXTENSION_OBJECT_TYPE)
 TYPE_CHECKER(Map, MAP_TYPE)
 TYPE_CHECKER(FixedDoubleArray, FIXED_DOUBLE_ARRAY_TYPE)
 TYPE_CHECKER(WeakFixedArray, FIXED_ARRAY_TYPE)
 TYPE_CHECKER(TransitionArray, TRANSITION_ARRAY_TYPE)
 
 
 bool Object::IsJSWeakCollection() const {
@@ skipping 1381 matching lines @@
     case JS_DATA_VIEW_TYPE:
       return JSDataView::kSize;
     case JS_SET_TYPE:
       return JSSet::kSize;
     case JS_MAP_TYPE:
       return JSMap::kSize;
     case JS_SET_ITERATOR_TYPE:
       return JSSetIterator::kSize;
     case JS_MAP_ITERATOR_TYPE:
       return JSMapIterator::kSize;
-    case JS_ITERATOR_RESULT_TYPE:
-      return JSIteratorResult::kSize;
     case JS_WEAK_MAP_TYPE:
       return JSWeakMap::kSize;
     case JS_WEAK_SET_TYPE:
       return JSWeakSet::kSize;
     case JS_PROMISE_TYPE:
       return JSObject::kHeaderSize;
     case JS_REGEXP_TYPE:
       return JSRegExp::kSize;
     case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
       return JSObject::kHeaderSize;
@@ skipping 1082 matching lines @@
 CAST_ACCESSOR(JSMap)
 CAST_ACCESSOR(JSMapIterator)
 CAST_ACCESSOR(JSMessageObject)
 CAST_ACCESSOR(JSModule)
 CAST_ACCESSOR(JSObject)
 CAST_ACCESSOR(JSProxy)
 CAST_ACCESSOR(JSReceiver)
 CAST_ACCESSOR(JSRegExp)
 CAST_ACCESSOR(JSSet)
 CAST_ACCESSOR(JSSetIterator)
-CAST_ACCESSOR(JSIteratorResult)
 CAST_ACCESSOR(JSTypedArray)
 CAST_ACCESSOR(JSValue)
 CAST_ACCESSOR(JSWeakMap)
 CAST_ACCESSOR(JSWeakSet)
 CAST_ACCESSOR(LayoutDescriptor)
 CAST_ACCESSOR(Map)
 CAST_ACCESSOR(Name)
 CAST_ACCESSOR(NameDictionary)
 CAST_ACCESSOR(NormalizedMapCache)
 CAST_ACCESSOR(Object)
@@ skipping 4501 matching lines @@
 
 Object* JSMapIterator::CurrentValue() {
   OrderedHashMap* table(OrderedHashMap::cast(this->table()));
   int index = Smi::cast(this->index())->value();
   Object* value = table->ValueAt(index);
   DCHECK(!value->IsTheHole());
   return value;
 }
 
 
-ACCESSORS(JSIteratorResult, done, Object, kDoneOffset)
-ACCESSORS(JSIteratorResult, value, Object, kValueOffset)
-
-
 String::SubStringRange::SubStringRange(String* string, int first, int length)
     : string_(string),
       first_(first),
       length_(length == -1 ? string->length() : length) {}
 
 
 class String::SubStringRange::iterator final {
  public:
   typedef std::forward_iterator_tag iterator_category;
   typedef int difference_type;
@@ skipping 87 matching lines @@
 #undef WRITE_INT64_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_OBJECTS_INL_H_