Attempt to fix some -Woverloaded-virtual warnings.

fpdfsdk/include/pdfwindow/PWL_ComboBox.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 _PWL_COMBOBOX_H_
 #define _PWL_COMBOBOX_H_
 
 class CPWL_CBEdit : public CPWL_Edit
 {
 public:
         CPWL_CBEdit(){};
         virtual ~CPWL_CBEdit(){};
 };
 
 class PWL_CLASS CPWL_CBListBox : public CPWL_ListBox
 {
 public:
         CPWL_CBListBox(){};
         virtual ~CPWL_CBListBox(){};
 
 public:
         virtual FX_BOOL                         OnLButtonUp(const CPDF_Point & point, FX_DWORD nFlag);
 
-        virtual FX_BOOL                         OnKeyDown(FX_WORD nChar, FX_BOOL & bExit, FX_DWORD nFlag);
-        virtual FX_BOOL                         OnChar(FX_WORD nChar, FX_BOOL & bExit, FX_DWORD nFlag);
+        FX_BOOL                         OnKeyDownWithExit(FX_WORD nChar, FX_BOOL & bExit, FX_DWORD nFlag);
+        FX_BOOL                         OnCharWithExit(FX_WORD nChar, FX_BOOL & bExit, FX_DWORD nFlag);
 };
 
 #define PWL_COMBOBOX_BUTTON_WIDTH               13
 
 class CPWL_CBButton : public CPWL_Wnd
 {
 public:
         CPWL_CBButton(){};
         virtual ~CPWL_CBButton(){};
 
@@ skipping 68 matching lines @@
         IPWL_Filler_Notify*                     m_pFillerNotify;
 
 public:
         void                                                    AttachFFLData(void* pData) {m_pFormFiller = pData;}
 private:
         void*                                                   m_pFormFiller;
 };
 
 #endif // !defined(AFX_PWL_COMBOBOX_H__9D6645F8_64AA_4806_94E8_95FDEDD39C17__INCLUDED_)