Implement <select> Popup Menu using PagePopup

Source/core/html/HTMLOptionElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 51 matching lines @@
     virtual bool isDisabledFormControl() const override;
 
     String textIndentedToRespectGroupLabel() const;
 
     void setSelectedState(bool);
 
     HTMLFormElement* form() const;
     bool spatialNavigationFocused() const;
 
     bool isDisplayNone() const;
+
+    int listIndex() const;
+
 private:
     explicit HTMLOptionElement(Document&);
 
     virtual bool rendererIsFocusable() const override { return true; }
     virtual void attach(const AttachContext& = AttachContext()) override;
     virtual void detach(const AttachContext& = AttachContext()) override;
     virtual void parseAttribute(const QualifiedName&, const AtomicString&) override;
     virtual InsertionNotificationRequest insertedInto(ContainerNode*) override;
     virtual void didNotifySubtreeInsertionsToDocument() override;
     virtual void removedFrom(ContainerNode*) override;
@@ skipping 12 matching lines @@
     void updateLabel();
 
     bool m_disabled;
     bool m_isSelected;
     RefPtr<RenderStyle> m_style;
 };
 
 } // namespace blink
 
 #endif // HTMLOptionElement_h