Fix CFWL_WidgetImpDelegate hierarchy.

xfa/src/fwl/src/basewidget/fwl_monthcalendarimp.cpp

Index: xfa/src/fwl/src/basewidget/fwl_monthcalendarimp.cpp
diff --git a/xfa/src/fwl/src/basewidget/fwl_monthcalendarimp.cpp b/xfa/src/fwl/src/basewidget/fwl_monthcalendarimp.cpp
index 7829105cc5e8773e9279f82eb25f7ef321d77d62..999f3249b6d924542bb838314d29ff6790ffa362 100644
--- a/xfa/src/fwl/src/basewidget/fwl_monthcalendarimp.cpp
+++ b/xfa/src/fwl/src/basewidget/fwl_monthcalendarimp.cpp
@@ -122,14 +122,12 @@ FX_DWORD CFWL_MonthCalendarImp::GetClassID() const {
 FWL_ERR CFWL_MonthCalendarImp::Initialize() {
   _FWL_ERR_CHECK_RETURN_VALUE_IF_FAIL(CFWL_WidgetImp::Initialize(),
                                       FWL_ERR_Indefinite);
-  m_pDelegate = (IFWL_WidgetDelegate*)new CFWL_MonthCalendarImpDelegate(this);
+  m_pDelegate = new CFWL_MonthCalendarImpDelegate(this);
   return FWL_ERR_Succeeded;
 }
 FWL_ERR CFWL_MonthCalendarImp::Finalize() {
-  if (m_pDelegate) {
-    delete (CFWL_MonthCalendarImpDelegate*)m_pDelegate;
-    m_pDelegate = NULL;
-  }
+  delete m_pDelegate;
+  m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
 FWL_ERR CFWL_MonthCalendarImp::GetWidgetRect(CFX_RectF& rect,