Fix virtual/override/final usage in Source/platform/.

Source/platform/image-decoders/gif/GIFImageDecoder.h

 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 23 matching lines @@
 
 typedef Vector<unsigned char> GIFRow;
 
 namespace blink {
 
 // This class decodes the GIF image format.
 class PLATFORM_EXPORT GIFImageDecoder : public ImageDecoder {
     WTF_MAKE_NONCOPYABLE(GIFImageDecoder);
 public:
     GIFImageDecoder(ImageSource::AlphaOption, ImageSource::GammaAndColorProfileOption, size_t maxDecodedBytes);
-    virtual ~GIFImageDecoder();
+    ~GIFImageDecoder() override;
 
     enum GIFParseQuery { GIFSizeQuery, GIFFrameCountQuery };
 
     // ImageDecoder:
-    virtual String filenameExtension() const override { return "gif"; }
-    virtual void setData(SharedBuffer* data, bool allDataReceived) override;
-    virtual int repetitionCount() const override;
-    virtual bool frameIsCompleteAtIndex(size_t) const override;
-    virtual float frameDurationAtIndex(size_t) const override;
-    virtual size_t clearCacheExceptFrame(size_t) override;
+    String filenameExtension() const override { return "gif"; }
+    void setData(SharedBuffer* data, bool allDataReceived) override;
+    int repetitionCount() const override;
+    bool frameIsCompleteAtIndex(size_t) const override;
+    float frameDurationAtIndex(size_t) const override;
+    size_t clearCacheExceptFrame(size_t) override;
     // CAUTION: setFailed() deletes |m_reader|.  Be careful to avoid
     // accessing deleted memory, especially when calling this from inside
     // GIFImageReader!
-    virtual bool setFailed() override;
+    bool setFailed() override;
 
     // Callbacks from the GIF reader.
     bool haveDecodedRow(size_t frameIndex, GIFRow::const_iterator rowBegin, size_t width, size_t rowNumber, unsigned repeatCount, bool writeTransparentPixels);
     bool frameComplete(size_t frameIndex);
 
     // For testing.
     bool parseCompleted() const;
 
 private:
     // ImageDecoder:
-    virtual void clearFrameBuffer(size_t frameIndex) override;
+    void clearFrameBuffer(size_t frameIndex) override;
     virtual void decodeSize() { parse(GIFSizeQuery); }
-    virtual size_t decodeFrameCount() override;
-    virtual void initializeNewFrame(size_t) override;
-    virtual void decode(size_t) override;
+    size_t decodeFrameCount() override;
+    void initializeNewFrame(size_t) override;
+    void decode(size_t) override;
 
     // Parses as much as is needed to answer the query, ignoring bitmap
     // data. If parsing fails, sets the "decode failure" flag.
     void parse(GIFParseQuery);
 
     // Called to initialize the frame buffer with the given index, based on
     // the previous frame's disposal method. Returns true on success. On
     // failure, this will mark the image as failed.
     bool initFrameBuffer(size_t frameIndex);
 
     bool m_currentBufferSawAlpha;
     mutable int m_repetitionCount;
     OwnPtr<GIFImageReader> m_reader;
 };
 
 } // namespace blink
 
 #endif