Use override in more classes in core/

core/src/fxcodec/codec/fx_codec.cpp

 // 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
 
 #include "../../../include/fxcodec/fx_codec.h"
 #include "codec_int.h"
 CCodec_ModuleMgr::CCodec_ModuleMgr()
     : m_pBasicModule(new CCodec_BasicModule),
@@ skipping 199 matching lines @@
 }
 FX_BOOL CCodec_BasicModule::A85Encode(const uint8_t* src_buf,
                                       FX_DWORD src_size,
                                       uint8_t*& dest_buf,
                                       FX_DWORD& dest_size) {
   return FALSE;
 }
 class CCodec_RLScanlineDecoder : public CCodec_ScanlineDecoder {
  public:
   CCodec_RLScanlineDecoder();
-  virtual ~CCodec_RLScanlineDecoder();
+  ~CCodec_RLScanlineDecoder() override;
+
   FX_BOOL Create(const uint8_t* src_buf,
                  FX_DWORD src_size,
                  int width,
                  int height,
                  int nComps,
                  int bpc);
-  virtual void v_DownScale(int dest_width, int dest_height) {}
-  virtual FX_BOOL v_Rewind();
-  virtual uint8_t* v_GetNextLine();
-  virtual FX_DWORD GetSrcOffset() { return m_SrcOffset; }
+
+  // CCodec_ScanlineDecoder
+  void v_DownScale(int dest_width, int dest_height) override {}
+  FX_BOOL v_Rewind() override;
+  uint8_t* v_GetNextLine() override;
+  FX_DWORD GetSrcOffset() override { return m_SrcOffset; }
 
  protected:
   FX_BOOL CheckDestSize();
   void GetNextOperator();
   void UpdateOperator(uint8_t used_bytes);
 
   uint8_t* m_pScanline;
   const uint8_t* m_pSrcBuf;
   FX_DWORD m_SrcSize;
   FX_DWORD m_dwLineBytes;
@@ skipping 158 matching lines @@
     int nComps,
     int bpc) {
   CCodec_RLScanlineDecoder* pRLScanlineDecoder = new CCodec_RLScanlineDecoder;
   if (!pRLScanlineDecoder->Create(src_buf, src_size, width, height, nComps,
                                   bpc)) {
     delete pRLScanlineDecoder;
     return NULL;
   }
   return pRLScanlineDecoder;
 }