Fold IFWL*::{Initialize|Finalize} into constructor/destructor

xfa/fwl/core/ifwl_datetimecalendar.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/ifwl_datetimecalendar.h"
 
+#include "third_party/base/ptr_util.h"
 #include "xfa/fwl/core/cfwl_widgetmgr.h"
 #include "xfa/fwl/core/ifwl_datetimepicker.h"
 #include "xfa/fwl/core/ifwl_formproxy.h"
 
 IFWL_DateTimeCalendar::IFWL_DateTimeCalendar(
     const IFWL_App* app,
     const CFWL_WidgetImpProperties& properties,
     IFWL_Widget* pOuter)
-    : IFWL_MonthCalendar(app, properties, pOuter) {}
-
-void IFWL_DateTimeCalendar::Initialize() {
-  IFWL_MonthCalendar::Initialize();
-
-  // Delete delegated set by IFWL_MonthCalendar::Initialize.
-  delete m_pDelegate;
-  m_pDelegate = new CFWL_DateTimeCalendarImpDelegate(this);
-}
-
-void IFWL_DateTimeCalendar::Finalize() {
-  delete m_pDelegate;
-  m_pDelegate = nullptr;
-  IFWL_MonthCalendar::Finalize();
+    : IFWL_MonthCalendar(app, properties, pOuter) {
+  SetDelegate(pdfium::MakeUnique<CFWL_DateTimeCalendarImpDelegate>(this));
 }
 
 CFWL_DateTimeCalendarImpDelegate::CFWL_DateTimeCalendarImpDelegate(
     IFWL_DateTimeCalendar* pOwner)
     : CFWL_MonthCalendarImpDelegate(pOwner), m_pOwner(pOwner) {
   m_bFlag = FALSE;
 }
 
 void CFWL_DateTimeCalendarImpDelegate::OnProcessMessage(
     CFWL_Message* pMessage) {
@@ skipping 165 matching lines @@
       rtInvalidate.Union(lpDatesInfo->rect);
     }
     m_pOwner->AddSelDay(iCurSel);
     IFWL_DateTimePicker* pDateTime =
         static_cast<IFWL_DateTimePicker*>(m_pOwner->m_pOuter);
     pDateTime->ProcessSelChanged(m_pOwner->m_iCurYear, m_pOwner->m_iCurMonth,
                                  iCurSel);
     pDateTime->ShowMonthCalendar(FALSE);
   }
 }