[builtins] implement JSBuiltinReducer for ArrayIteratorNext()

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 6c189947a7b17abd52a1c503a810e9c0c764532e..ddc6e8919106c6835d7f062fec7bce9763771b0d 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -7277,6 +7277,10 @@ enum BuiltinFunctionId {
   kMathPowHalf,
   // These are manually assigned to special getters during bootstrapping.
   kArrayBufferByteLength,
+  kArrayEntries,
+  kArrayKeys,
+  kArrayValues,
+  kArrayIteratorNext,
   kDataViewBuffer,
   kDataViewByteLength,
   kDataViewByteOffset,
@@ -7290,7 +7294,10 @@ enum BuiltinFunctionId {
   kGlobalIsNaN,
   kTypedArrayByteLength,
   kTypedArrayByteOffset,
+  kTypedArrayEntries,
+  kTypedArrayKeys,
   kTypedArrayLength,
+  kTypedArrayValues,
   kSharedArrayBufferByteLength,
   kStringIterator,
   kStringIteratorNext,
@@ -10707,6 +10714,10 @@ class JSArrayIterator : public JSObject {
   // allocated.
   DECL_ACCESSORS(object_map, Object)
 
+  // Return the ElementsKind that a JSArrayIterator's [[IteratedObject]] is
+  // expected to have, based on its instance type.
+  static ElementsKind ElementsKindForInstanceType(InstanceType instance_type);
+
   static const int kIteratedObjectOffset = JSObject::kHeaderSize;
   static const int kNextIndexOffset = kIteratedObjectOffset + kPointerSize;
   static const int kIteratedObjectMapOffset = kNextIndexOffset + kPointerSize;