Continue nit cleanup in fwl/core

xfa/fwl/core/cfwl_combobox.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/cfwl_combobox.h"
 
 #include <utility>
 
 #include "third_party/base/ptr_util.h"
 #include "xfa/fwl/core/fwl_error.h"
 #include "xfa/fwl/core/ifwl_widget.h"
 
 namespace {
 
 IFWL_ComboBox* ToComboBox(IFWL_Widget* widget) {
   return static_cast<IFWL_ComboBox*>(widget);
 }
 
-const IFWL_ComboBox* ToComboBox(const IFWL_Widget* widget) {
-  return static_cast<const IFWL_ComboBox*>(widget);
-}
-
 }  // namespace
 
 CFWL_ComboBox::CFWL_ComboBox(const IFWL_App* app)
     : CFWL_Widget(app), m_fMaxListHeight(0) {}
 
 CFWL_ComboBox::~CFWL_ComboBox() {}
 
 void CFWL_ComboBox::Initialize() {
   ASSERT(!m_pIface);
 
@@ skipping 210 matching lines @@
 
 void CFWL_ComboBox::SetItemCheckState(IFWL_Widget* pWidget,
                                       CFWL_ListItem* pItem,
                                       uint32_t dwCheckState) {
   static_cast<CFWL_ListItem*>(pItem)->m_dwCheckState = dwCheckState;
 }
 
 FX_FLOAT CFWL_ComboBox::GetListHeight(IFWL_Widget* pWidget) {
   return m_fMaxListHeight;
 }