Use override in more classes in fpdfsdk/

fpdfsdk/include/formfiller/FFL_ListBox.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 FPDFSDK_INCLUDE_FORMFILLER_FFL_LISTBOX_H_
 #define FPDFSDK_INCLUDE_FORMFILLER_FFL_LISTBOX_H_
 
 #include <set>
 
 #include "FFL_FormFiller.h"
 
 class CBA_FontMap;
 
 class CFFL_ListBox : public CFFL_FormFiller {
  public:
   CFFL_ListBox(CPDFDoc_Environment* pApp, CPDFSDK_Annot* pWidget);
-  virtual ~CFFL_ListBox();
+  ~CFFL_ListBox() override;
 
-  virtual PWL_CREATEPARAM GetCreateParam();
-  virtual CPWL_Wnd* NewPDFWindow(const PWL_CREATEPARAM& cp,
-                                 CPDFSDK_PageView* pPageView);
-
-  virtual FX_BOOL OnChar(CPDFSDK_Annot* pAnnot, FX_UINT nChar, FX_UINT nFlags);
-
-  virtual FX_BOOL IsDataChanged(CPDFSDK_PageView* pPageView);
-  virtual void SaveData(CPDFSDK_PageView* pPageView);
-
-  virtual void GetActionData(CPDFSDK_PageView* pPageView,
-                             CPDF_AAction::AActionType type,
-                             PDFSDK_FieldAction& fa);
-  virtual void SetActionData(CPDFSDK_PageView* pPageView,
-                             CPDF_AAction::AActionType type,
-                             const PDFSDK_FieldAction& fa);
-
-  virtual void SaveState(CPDFSDK_PageView* pPageView);
-  virtual void RestoreState(CPDFSDK_PageView* pPageView);
-
-  virtual CPWL_Wnd* ResetPDFWindow(CPDFSDK_PageView* pPageView,
-                                   FX_BOOL bRestoreValue);
-  virtual void OnKeyStroke(FX_BOOL bKeyDown, FX_DWORD nFlag);
+  // CFFL_FormFiller
+  PWL_CREATEPARAM GetCreateParam() override;
+  CPWL_Wnd* NewPDFWindow(const PWL_CREATEPARAM& cp,
+                         CPDFSDK_PageView* pPageView) override;
+  FX_BOOL OnChar(CPDFSDK_Annot* pAnnot, FX_UINT nChar, FX_UINT nFlags) override;
+  FX_BOOL IsDataChanged(CPDFSDK_PageView* pPageView) override;
+  void SaveData(CPDFSDK_PageView* pPageView) override;
+  void GetActionData(CPDFSDK_PageView* pPageView,
+                     CPDF_AAction::AActionType type,
+                     PDFSDK_FieldAction& fa) override;
+  void SetActionData(CPDFSDK_PageView* pPageView,
+                     CPDF_AAction::AActionType type,
+                     const PDFSDK_FieldAction& fa) override;
+  void SaveState(CPDFSDK_PageView* pPageView) override;
+  void RestoreState(CPDFSDK_PageView* pPageView) override;
+  CPWL_Wnd* ResetPDFWindow(CPDFSDK_PageView* pPageView,
+                           FX_BOOL bRestoreValue) override;
+  void OnKeyStroke(FX_BOOL bKeyDown, FX_DWORD nFlag) override;
 
  private:
   CBA_FontMap* m_pFontMap;
   std::set<int> m_OriginSelections;
   CFX_ArrayTemplate<int> m_State;
 };
 
 #endif  // FPDFSDK_INCLUDE_FORMFILLER_FFL_LISTBOX_H_