[builtins] implement JSBuiltinReducer for ArrayIteratorNext()

src/isolate-inl.h

 // Copyright 2015 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_ISOLATE_INL_H_
 #define V8_ISOLATE_INL_H_
 
 #include "src/isolate.h"
 #include "src/objects-inl.h"
 
@@ skipping 125 matching lines @@
 bool Isolate::IsHasInstanceLookupChainIntact() {
   PropertyCell* has_instance_cell = heap()->has_instance_protector();
   return has_instance_cell->value() == Smi::FromInt(kArrayProtectorValid);
 }
 
 bool Isolate::IsStringLengthOverflowIntact() {
   PropertyCell* has_instance_cell = heap()->string_length_protector();
   return has_instance_cell->value() == Smi::FromInt(kArrayProtectorValid);
 }
 
+bool Isolate::IsFastArrayIterationIntact() {
+  Cell* fast_iteration = heap()->fast_array_iteration_protector();
+  return fast_iteration->value() == Smi::FromInt(kArrayProtectorValid);
+}
+
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ISOLATE_INL_H_