Use override in more classes in fpdfsdk/

fpdfsdk/include/formfiller/FFL_ListBox.h

Index: fpdfsdk/include/formfiller/FFL_ListBox.h
diff --git a/fpdfsdk/include/formfiller/FFL_ListBox.h b/fpdfsdk/include/formfiller/FFL_ListBox.h
index 2e26069e2cc080c1a6c2b298a57b374931743243..01ad2218d02a38cb64409a3c0fcfe541df12677c 100644
--- a/fpdfsdk/include/formfiller/FFL_ListBox.h
+++ b/fpdfsdk/include/formfiller/FFL_ListBox.h
@@ -16,30 +16,26 @@ class CBA_FontMap;
 class CFFL_ListBox : public CFFL_FormFiller {
  public:
   CFFL_ListBox(CPDFDoc_Environment* pApp, CPDFSDK_Annot* pWidget);
-  virtual ~CFFL_ListBox();
-
-  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_ListBox() override;
+
+  // 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;