Use override in more classes in core/

core/include/fpdfdoc/fpdf_ap.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_FPDFDOC_FPDF_AP_H_
 #define CORE_INCLUDE_FPDFDOC_FPDF_AP_H_
 
 #include "../fpdfapi/fpdf_parser.h"
@@ skipping 33 matching lines @@
 
   int32_t nColorType;
   FX_FLOAT fColor1;
   FX_FLOAT fColor2;
   FX_FLOAT fColor3;
   FX_FLOAT fColor4;
 };
 class CPVT_Provider : public IPDF_VariableText_Provider {
  public:
   CPVT_Provider(IPVT_FontMap* pFontMap);
+  ~CPVT_Provider() override;
 
-  virtual ~CPVT_Provider();
-
-  int32_t GetCharWidth(int32_t nFontIndex, FX_WORD word, int32_t nWordStyle);
-
-  int32_t GetTypeAscent(int32_t nFontIndex);
-
-  int32_t GetTypeDescent(int32_t nFontIndex);
-
-  int32_t GetWordFontIndex(FX_WORD word, int32_t charset, int32_t nFontIndex);
-
-  FX_BOOL IsLatinWord(FX_WORD word);
-
-  int32_t GetDefaultFontIndex();
+  // IPDF_VariableText_Provider
+  int32_t GetCharWidth(int32_t nFontIndex,
+                       FX_WORD word,
+                       int32_t nWordStyle) override;
+  int32_t GetTypeAscent(int32_t nFontIndex) override;
+  int32_t GetTypeDescent(int32_t nFontIndex) override;
+  int32_t GetWordFontIndex(FX_WORD word,
+                           int32_t charset,
+                           int32_t nFontIndex) override;
+  FX_BOOL IsLatinWord(FX_WORD word) override;
+  int32_t GetDefaultFontIndex() override;
 
  private:
   IPVT_FontMap* m_pFontMap;
 };
 #define PBS_SOLID 0
 #define PBS_DASH 1
 #define PBS_BEVELED 2
 #define PBS_INSET 3
 #define PBS_UNDERLINED 4
 class CPVT_GenerateAP {
@@ skipping 20 matching lines @@
                                          const CPVT_Color& crLeftTop,
                                          const CPVT_Color& crRightBottom,
                                          int32_t nStyle,
                                          const CPVT_Dash& dash);
 
   static CFX_ByteString GenerateColorAP(const CPVT_Color& color,
                                         const FX_BOOL& bFillOrStroke);
 };
 
 #endif  // CORE_INCLUDE_FPDFDOC_FPDF_AP_H_