Remove the GetCaption dataprovider method

xfa/fwl/core/cfwl_datetimepicker.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_CORE_CFWL_DATETIMEPICKER_H_
 #define XFA_FWL_CORE_CFWL_DATETIMEPICKER_H_
 
 #include "xfa/fwl/core/cfwl_widget.h"
 #include "xfa/fwl/core/ifwl_datetimepicker.h"
 
 class CFWL_DateTimePicker : public CFWL_Widget,
                             public IFWL_DateTimePicker::DataProvider {
  public:
   explicit CFWL_DateTimePicker(const IFWL_App* pApp);
   ~CFWL_DateTimePicker() override;
 
   void Initialize();
 
-  // IFWL_Widget::DataProvider
-  void GetCaption(IFWL_Widget* pWidget, CFX_WideString& wsCaption) override;
-
   // IFWL_DateTimePicker::DataProvider
   void GetToday(IFWL_Widget* pWidget,
                 int32_t& iYear,
                 int32_t& iMonth,
                 int32_t& iDay) override;
 
   void GetEditText(CFX_WideString& wsText);
   void SetEditText(const CFX_WideString& wsText);
 
   int32_t CountSelRanges();
   int32_t GetSelRange(int32_t nIndex, int32_t& nStart);
 
   void SetCurSel(int32_t iYear, int32_t iMonth, int32_t iDay);
   void GetBBox(CFX_RectF& rect);
   void SetEditLimit(int32_t nLimit);
   void ModifyEditStylesEx(uint32_t dwStylesExAdded, uint32_t dwStylesExRemoved);
 };
 
 #endif  // XFA_FWL_CORE_CFWL_DATETIMEPICKER_H_