Store object definition ID in each js_class.

fpdfsdk/include/javascript/Icon.h

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef FPDFSDK_INCLUDE_JAVASCRIPT_ICON_H_
 #define FPDFSDK_INCLUDE_JAVASCRIPT_ICON_H_
 
 #include "JS_Define.h"
@@ skipping 12 matching lines @@
  private:
   CPDF_Stream* m_pIconStream;
   CFX_WideString m_swIconName;
 };
 
 class CJS_Icon : public CJS_Object {
  public:
   CJS_Icon(v8::Local<v8::Object> pObject) : CJS_Object(pObject) {}
   ~CJS_Icon() override {}
 
- public:
-  DECLARE_JS_CLASS(CJS_Icon);
-
+  DECLARE_JS_CLASS();
   JS_STATIC_PROP(name, Icon);
 };
 
 #endif  // FPDFSDK_INCLUDE_JAVASCRIPT_ICON_H_