Remove SetDataProvider from IFWL_Widget

xfa/fwl/core/fwl_formimp.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/fwl/core/fwl_formimp.h"
 
 #include "xfa/fde/tto/fde_textout.h"
 #include "xfa/fwl/basewidget/fwl_formproxyimp.h"
@@ skipping 739 matching lines @@
   CFX_DIBitmap* pSmallIcon = pData->GetIcon(m_pInterface, FALSE);
   if (pBigIcon)
     m_pBigIcon = pBigIcon;
   if (pSmallIcon)
     m_pSmallIcon = pSmallIcon;
 }
 void CFWL_FormImp::UpdateCaption() {
   CFWL_WidgetMgr* pWidgetMgr = CFWL_WidgetMgr::GetInstance();
   if (!pWidgetMgr)
     return;
-  IFWL_FormDP* pData =
-      static_cast<IFWL_FormDP*>(m_pProperties->m_pDataProvider);
+  IFWL_DataProvider* pData = m_pProperties->m_pDataProvider;
   if (!pData)
     return;
   CFX_WideString text;
   pData->GetCaption(m_pInterface, text);
 }
 void CFWL_FormImp::DoWidthLimit(FX_FLOAT& fLeft,
                                 FX_FLOAT& fWidth,
                                 FX_FLOAT fCurX,
                                 FX_FLOAT fSpace,
                                 FX_FLOAT fLimitMin,
@@ skipping 363 matching lines @@
 
 uint32_t CFWL_SysBtn::GetPartState() const {
   if (IsDisabled())
     return CFWL_PartState_Disabled;
   if (m_dwState & FWL_SYSBUTTONSTATE_Pressed)
     return CFWL_PartState_Pressed;
   if (m_dwState & FWL_SYSBUTTONSTATE_Hover)
     return CFWL_PartState_Hovered;
   return CFWL_PartState_Normal;
 }