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

Source/platform/graphics/filters/FEDisplacementMap.h

Index: Source/platform/graphics/filters/FEDisplacementMap.h
diff --git a/Source/platform/graphics/filters/FEDisplacementMap.h b/Source/platform/graphics/filters/FEDisplacementMap.h
index 04eceba7eea449fef1bb107462c514253cce774c..06998ba6777fcf64e16c8bf11f4e07fc7b7a9848 100644
--- a/Source/platform/graphics/filters/FEDisplacementMap.h
+++ b/Source/platform/graphics/filters/FEDisplacementMap.h
@@ -48,16 +48,16 @@ public:
     float scale() const;
     bool setScale(float);
 
-    virtual FloatRect mapPaintRect(const FloatRect&, bool forward = true) override final;
+    FloatRect mapPaintRect(const FloatRect&, bool forward = true) final;
 
-    virtual TextStream& externalRepresentation(TextStream&, int indention) const override;
+    TextStream& externalRepresentation(TextStream&, int indention) const override;
 
     FloatRect determineAbsolutePaintRect(const FloatRect& requestedRect) override;
 
 private:
     FEDisplacementMap(Filter*, ChannelSelectorType xChannelSelector, ChannelSelectorType yChannelSelector, float);
 
-    virtual PassRefPtr<SkImageFilter> createImageFilter(SkiaImageFilterBuilder*) override;
+    PassRefPtr<SkImageFilter> createImageFilter(SkiaImageFilterBuilder*) override;
 
     ChannelSelectorType m_xChannelSelector;
     ChannelSelectorType m_yChannelSelector;