Fix virtual/override/final usage in Source/core/layout/.

Source/core/layout/LayoutSlider.h

Index: Source/core/layout/LayoutSlider.h
diff --git a/Source/core/layout/LayoutSlider.h b/Source/core/layout/LayoutSlider.h
index 16fd2535510b676f1b2dff4cbadd641213b3409c..57745229be9a7a2b0d84ecb9bb81f670226334bb 100644
--- a/Source/core/layout/LayoutSlider.h
+++ b/Source/core/layout/LayoutSlider.h
@@ -33,18 +33,18 @@ public:
     static const int defaultTrackLength;
 
     explicit LayoutSlider(HTMLInputElement*);
-    virtual ~LayoutSlider();
+    ~LayoutSlider() override;
 
     bool inDragMode() const;
 
-    virtual const char* name() const override { return "LayoutSlider"; }
+    const char* name() const override { return "LayoutSlider"; }
 
 private:
-    virtual bool isOfType(LayoutObjectType type) const override { return type == LayoutObjectSlider || LayoutFlexibleBox::isOfType(type); }
+    bool isOfType(LayoutObjectType type) const override { return type == LayoutObjectSlider || LayoutFlexibleBox::isOfType(type); }
 
-    virtual int baselinePosition(FontBaseline, bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const override;
-    virtual void computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const override;
-    virtual void layout() override;
+    int baselinePosition(FontBaseline, bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const override;
+    void computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const override;
+    void layout() override;
 
     SliderThumbElement* sliderThumbElement() const;
 };