Use override in more classes in core/

core/include/fpdfapi/fpdf_resource.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 CORE_INCLUDE_FPDFAPI_FPDF_RESOURCE_H_
 #define CORE_INCLUDE_FPDFAPI_FPDF_RESOURCE_H_
 
 #include "../fxcrt/fx_system.h"
@@ skipping 646 matching lines @@
   CPDF_Pattern(const CFX_AffineMatrix* pParentMatrix);
   FX_BOOL m_bForceClear;
 };
 
 class CPDF_TilingPattern : public CPDF_Pattern {
  public:
   CPDF_TilingPattern(CPDF_Document* pDoc,
                      CPDF_Object* pPatternObj,
                      const CFX_AffineMatrix* parentMatrix);
 
-  virtual ~CPDF_TilingPattern();
+  ~CPDF_TilingPattern() override;
 
   FX_BOOL Load();
 
   FX_BOOL m_bColored;
 
   CFX_FloatRect m_BBox;
 
   FX_FLOAT m_XStep;
 
   FX_FLOAT m_YStep;
 
   CPDF_Form* m_pForm;
 };
 class CPDF_ShadingPattern : public CPDF_Pattern {
  public:
   CPDF_ShadingPattern(CPDF_Document* pDoc,
                       CPDF_Object* pPatternObj,
                       FX_BOOL bShading,
                       const CFX_AffineMatrix* parentMatrix);
 
-  virtual ~CPDF_ShadingPattern();
+  ~CPDF_ShadingPattern() override;
 
   CPDF_Object* m_pShadingObj;
 
   FX_BOOL m_bShadingObj;
 
   FX_BOOL Load();
 
   FX_BOOL Reload();
 
   int m_ShadingType;
@@ skipping 134 matching lines @@
 
   FX_BOOL m_bInterpolate;
 
   CPDF_Document* m_pDocument;
 
   CPDF_Dictionary* m_pOC;
   CPDF_Dictionary* InitJPEG(uint8_t* pData, FX_DWORD size);
 };
 
 #endif  // CORE_INCLUDE_FPDFAPI_FPDF_RESOURCE_H_