Make code compile with clang_use_chrome_plugin (part III)

xfa/fxbarcode/qrcode/BC_QRCodeWriter.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 XFA_FXBARCODE_QRCODE_BC_QRCODEWRITER_H_
 #define XFA_FXBARCODE_QRCODE_BC_QRCODEWRITER_H_
 
 #include "xfa/fxbarcode/BC_TwoDimWriter.h"
 
 class CBC_TwoDimWriter;
 class CBC_QRCodeWriter : public CBC_TwoDimWriter {
  public:
   CBC_QRCodeWriter();
-  virtual ~CBC_QRCodeWriter();
+  ~CBC_QRCodeWriter() override;
+
   uint8_t* Encode(const CFX_WideString& contents,
                   int32_t ecLevel,
                   int32_t& outWidth,
                   int32_t& outHeight,
                   int32_t& e);
   uint8_t* Encode(const CFX_ByteString& contents,
                   BCFORMAT format,
                   int32_t& outWidth,
                   int32_t& outHeight,
                   int32_t hints,
                   int32_t& e);
   uint8_t* Encode(const CFX_ByteString& contents,
                   BCFORMAT format,
                   int32_t& outWidth,
                   int32_t& outHeight,
                   int32_t& e);
   FX_BOOL SetVersion(int32_t version);
-  FX_BOOL SetErrorCorrectionLevel(int32_t level);
+
+  // CBC_TwoDimWriter
+  FX_BOOL SetErrorCorrectionLevel(int32_t level) override;
+
   static void ReleaseAll();
 
  private:
   int32_t m_iVersion;
 };
 
 #endif  // XFA_FXBARCODE_QRCODE_BC_QRCODEWRITER_H_