Use override in more classes in fpdfsdk/

fpdfsdk/include/javascript/Icon.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_JAVASCRIPT_ICON_H_
 #define FPDFSDK_INCLUDE_JAVASCRIPT_ICON_H_
 
 #include "JS_Define.h"
 
 class Icon : public CJS_EmbedObj {
  public:
   Icon(CJS_Object* pJSObject);
-  virtual ~Icon();
+  ~Icon() override;
+
   FX_BOOL name(IFXJS_Context* cc, CJS_PropValue& vp, CFX_WideString& sError);
   void SetStream(CPDF_Stream* pIconStream);
   CPDF_Stream* GetStream();
   void SetIconName(CFX_WideString name);
   CFX_WideString GetIconName();
 
  private:
   CPDF_Stream* m_pIconStream;
   CFX_WideString m_swIconName;
 };
 
 class CJS_Icon : public CJS_Object {
  public:
-  CJS_Icon(JSFXObject pObject) : CJS_Object(pObject){};
-  virtual ~CJS_Icon(){};
+  CJS_Icon(JSFXObject pObject) : CJS_Object(pObject) {}
+  ~CJS_Icon() override {}
 
  public:
   DECLARE_JS_CLASS(CJS_Icon);
 
   JS_STATIC_PROP(name, Icon);
 };
 
 #endif  // FPDFSDK_INCLUDE_JAVASCRIPT_ICON_H_