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

Source/core/layout/svg/LayoutSVGGradientStop.h

Index: Source/core/layout/svg/LayoutSVGGradientStop.h
diff --git a/Source/core/layout/svg/LayoutSVGGradientStop.h b/Source/core/layout/svg/LayoutSVGGradientStop.h
index 69316c275f8df7936b0a28a16179669c7cc01f0d..5b8d4fb931b94790a3cb7db8977a59b780eb91f9 100644
--- a/Source/core/layout/svg/LayoutSVGGradientStop.h
+++ b/Source/core/layout/svg/LayoutSVGGradientStop.h
@@ -32,23 +32,23 @@ class SVGStopElement;
 class LayoutSVGGradientStop final : public LayoutObject {
 public:
     explicit LayoutSVGGradientStop(SVGStopElement*);
-    virtual ~LayoutSVGGradientStop();
+    ~LayoutSVGGradientStop() override;
 
-    virtual const char* name() const override { return "LayoutSVGGradientStop"; }
-    virtual bool isOfType(LayoutObjectType type) const override { return type == LayoutObjectSVG || type == LayoutObjectSVGGradientStop || LayoutObject::isOfType(type); }
+    const char* name() const override { return "LayoutSVGGradientStop"; }
+    bool isOfType(LayoutObjectType type) const override { return type == LayoutObjectSVG || type == LayoutObjectSVGGradientStop || LayoutObject::isOfType(type); }
 
-    virtual void layout() override;
+    void layout() override;
 
     // This overrides are needed to prevent ASSERTs on <svg><stop /></svg>
     // LayoutObject's default implementations ASSERT_NOT_REACHED()
     // https://bugs.webkit.org/show_bug.cgi?id=20400
-    virtual LayoutRect clippedOverflowRectForPaintInvalidation(const LayoutBoxModelObject*, const PaintInvalidationState* = nullptr) const override { return LayoutRect(); }
-    virtual FloatRect objectBoundingBox() const override { return FloatRect(); }
-    virtual FloatRect strokeBoundingBox() const override { return FloatRect(); }
-    virtual FloatRect paintInvalidationRectInLocalCoordinates() const override { return FloatRect(); }
+    LayoutRect clippedOverflowRectForPaintInvalidation(const LayoutBoxModelObject*, const PaintInvalidationState* = nullptr) const override { return LayoutRect(); }
+    FloatRect objectBoundingBox() const override { return FloatRect(); }
+    FloatRect strokeBoundingBox() const override { return FloatRect(); }
+    FloatRect paintInvalidationRectInLocalCoordinates() const override { return FloatRect(); }
 
 protected:
-    virtual void styleDidChange(StyleDifference, const ComputedStyle* oldStyle) override;
+    void styleDidChange(StyleDifference, const ComputedStyle* oldStyle) override;
 
 private:
     SVGGradientElement* gradientElement() const;