Use virtual function to retrieve interface pointer

xfa/fwl/lightwidget/cfwl_picturebox.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 XFA_FWL_LIGHTWIDGET_CFWL_PICTUREBOX_H_
 #define XFA_FWL_LIGHTWIDGET_CFWL_PICTUREBOX_H_
 
 #include "xfa/fwl/basewidget/ifwl_picturebox.h"
 #include "xfa/fwl/core/fwl_error.h"
 #include "xfa/fwl/lightwidget/cfwl_widget.h"
 
 class CFWL_PictureBox : public CFWL_Widget {
  public:
   CFWL_PictureBox();
   ~CFWL_PictureBox() override;
 
+  IFWL_PictureBox* GetWidget() override;
+  const IFWL_PictureBox* GetWidget() const override;
+
   static CFWL_PictureBox* Create();
 
   FWL_Error Initialize(const CFWL_WidgetProperties* pProperties = nullptr);
   CFX_DIBitmap* GetPicture();
   FWL_Error SetPicture(CFX_DIBitmap* pBitmap);
   FX_FLOAT GetRotation();
   FWL_Error SetRotation(FX_FLOAT fRotation);
   int32_t GetFlipMode();
   FWL_Error SetFlipMode(int32_t iFlipMode);
   int32_t GetOpacity();
@@ skipping 28 matching lines @@
     FX_FLOAT m_fScaleY;
     FX_FLOAT m_fOffSetX;
     FX_FLOAT m_fOffSetY;
     CFX_WideString m_wsData;
   };
 
   CFWL_PictureBoxDP m_PictureBoxDP;
 };
 
 #endif  // XFA_FWL_LIGHTWIDGET_CFWL_PICTUREBOX_H_