Add GetPropertyAttribute method for Object in the API

include/v8.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1440 matching lines @@
   //
   // Note also that this only works for named properties.
   V8EXPORT bool ForceSet(Handle<Value> key,
                          Handle<Value> value,
                          PropertyAttribute attribs = None);
 
   V8EXPORT Local<Value> Get(Handle<Value> key);
 
   V8EXPORT Local<Value> Get(uint32_t index);
 
+  /**
+   * Gets the property attributes of a property.
+   * Can be None or any combination of ReadOnly, DontEnum and DontDelete.
+   *
+   * Note: Returns None when the property doesn't exist.
+   */
+  V8EXPORT PropertyAttribute GetPropertyAttributes(Handle<Value> key);
+
   // TODO(1245389): Replace the type-specific versions of these
   // functions with generic ones that accept a Handle<Value> key.
   V8EXPORT bool Has(Handle<String> key);
 
   V8EXPORT bool Delete(Handle<String> key);
 
   // Delete a property on this object bypassing interceptors and
   // ignoring dont-delete attributes.
   V8EXPORT bool ForceDelete(Handle<Value> key);
 
@@ skipping 2724 matching lines @@
 
 
 }  // namespace v8
 
 
 #undef V8EXPORT
 #undef TYPE_CHECK
 
 
 #endif  // V8_H_