Handle Object.observe notifications for setting Array.length

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index f245d97d8ba717f670823475f54fa64283ae991e..7925413ab7b3bc7f4d13da27e5014f5eb78ea52c 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -2208,6 +2208,12 @@ class JSObject: public JSReceiver {
     static inline int SizeOf(Map* map, HeapObject* object);
   };
 
+  // Enqueue change record for Object.observe. May cause GC.
+  static void EnqueueChangeRecord(Handle<JSObject> object,
+                                  const char* type,
+                                  Handle<String> name,
+                                  Handle<Object> old_value);
+
  private:
   friend class DictionaryElementsAccessor;
 
@@ -2313,11 +2319,6 @@ class JSObject: public JSReceiver {
   MUST_USE_RESULT MaybeObject* SetHiddenPropertiesHashTable(
       Object* value);
 
-  // Enqueue change record for Object.observe. May cause GC.
-  void EnqueueChangeRecord(const char* type,
-                           Handle<String> name,
-                           Handle<Object> old_value);
-
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSObject);
 };