Use virtual function to retrieve interface pointer

xfa/fxfa/app/xfa_ffimageedit.cpp

 // 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
 
 #include "xfa/fxfa/app/xfa_ffimageedit.h"
 
 #include "xfa/fwl/core/cfwl_message.h"
 #include "xfa/fwl/core/fwl_noteimp.h"
@@ skipping 79 matching lines @@
 
   if (!PtInActiveRect(fx, fy))
     return FALSE;
 
   SetButtonDown(TRUE);
   CFWL_MsgMouse ms;
   ms.m_dwCmd = FWL_MouseCommand::LeftButtonDown;
   ms.m_dwFlags = dwFlags;
   ms.m_fx = fx;
   ms.m_fy = fy;
-  ms.m_pDstTarget = m_pNormalWidget->m_pIface;
+  ms.m_pDstTarget = m_pNormalWidget->GetWidget();
   FWLToClient(ms.m_fx, ms.m_fy);
   TranslateFWLMessage(&ms);
   return TRUE;
 }
 
 void CXFA_FFImageEdit::SetFWLRect() {
   if (!m_pNormalWidget) {
     return;
   }
   CFX_RectF rtUIMargin;
@@ skipping 18 matching lines @@
 
 void CXFA_FFImageEdit::OnProcessEvent(CFWL_Event* pEvent) {
   CXFA_FFField::OnProcessEvent(pEvent);
   m_pOldDelegate->OnProcessEvent(pEvent);
 }
 
 void CXFA_FFImageEdit::OnDrawWidget(CFX_Graphics* pGraphics,
                                     const CFX_Matrix* pMatrix) {
   m_pOldDelegate->OnDrawWidget(pGraphics, pMatrix);
 }