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

Source/platform/scroll/ScrollAnimatorNone.h

Index: Source/platform/scroll/ScrollAnimatorNone.h
diff --git a/Source/platform/scroll/ScrollAnimatorNone.h b/Source/platform/scroll/ScrollAnimatorNone.h
index fb8b8f819c9f68d467aa37223818ec44dbf583ea..e5ca5c79c6150a0f052f3e24dcf7d8db7771f71c 100644
--- a/Source/platform/scroll/ScrollAnimatorNone.h
+++ b/Source/platform/scroll/ScrollAnimatorNone.h
@@ -42,19 +42,19 @@ class ScrollAnimatorNoneTest;
 class PLATFORM_EXPORT ScrollAnimatorNone : public ScrollAnimator {
 public:
     explicit ScrollAnimatorNone(ScrollableArea*);
-    virtual ~ScrollAnimatorNone();
+    ~ScrollAnimatorNone() override;
 
-    virtual ScrollResultOneDimensional userScroll(ScrollbarOrientation, ScrollGranularity, float step, float delta) override;
-    virtual void scrollToOffsetWithoutAnimation(const FloatPoint&) override;
+    ScrollResultOneDimensional userScroll(ScrollbarOrientation, ScrollGranularity, float step, float delta) override;
+    void scrollToOffsetWithoutAnimation(const FloatPoint&) override;
 
-    virtual void cancelAnimations() override;
-    virtual void serviceScrollAnimations() override;
-    virtual bool hasRunningAnimation() const override;
+    void cancelAnimations() override;
+    void serviceScrollAnimations() override;
+    bool hasRunningAnimation() const override;
 
-    virtual void updateAfterLayout() override;
-    virtual void willEndLiveResize() override;
-    virtual void didAddVerticalScrollbar(Scrollbar*) override;
-    virtual void didAddHorizontalScrollbar(Scrollbar*) override;
+    void updateAfterLayout() override;
+    void willEndLiveResize() override;
+    void didAddVerticalScrollbar(Scrollbar*) override;
+    void didAddHorizontalScrollbar(Scrollbar*) override;
 
     enum Curve {
         Linear,