Add remaining @@toStringTag symbols to builtins

src/array-iterator.js

Index: src/array-iterator.js
diff --git a/src/array-iterator.js b/src/array-iterator.js
index 5ced9da17cf5f654bd27e7031734743277260054..864d5c1fc2aa92b6fd2b5b8a2c1e316a412b5139 100644
--- a/src/array-iterator.js
+++ b/src/array-iterator.js
@@ -112,6 +112,8 @@ function SetUpArrayIterator() {
   %FunctionSetName(ArrayIteratorIterator, '[Symbol.iterator]');
   %AddNamedProperty(ArrayIterator.prototype, symbolIterator,
                     ArrayIteratorIterator, DONT_ENUM);
+  %AddNamedProperty(ArrayIterator.prototype, symbolToStringTag,
+                    "Array Iterator", READ_ONLY | DONT_ENUM);
 }
 SetUpArrayIterator();