[builtins] implement JSBuiltinReducer for ArrayIteratorNext()

src/isolate.h

Index: src/isolate.h
diff --git a/src/isolate.h b/src/isolate.h
index 33e395f8ecc70a8d4468b941b3204f83030b6e9a..67a751d4ae2b79d3adcef51f48ee2185071577b9 100644
--- a/src/isolate.h
+++ b/src/isolate.h
@@ -997,6 +997,9 @@ class Isolate {
   bool IsIsConcatSpreadableLookupChainIntact(JSReceiver* receiver);
   inline bool IsStringLengthOverflowIntact();
 
+  // Avoid deopt loops if fast Array Iterators migrate to slow Array Iterators.
+  inline bool IsFastArrayIterationIntact();
+
   // On intent to set an element in object, make sure that appropriate
   // notifications occur if the set is on the elements of the array or
   // object prototype. Also ensure that changes to prototype chain between