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

Source/platform/graphics/paint/ScrollDisplayItem.h

Index: Source/platform/graphics/paint/ScrollDisplayItem.h
diff --git a/Source/platform/graphics/paint/ScrollDisplayItem.h b/Source/platform/graphics/paint/ScrollDisplayItem.h
index 7c16b6fe92e0e1021a9ffffdbd1a5f8f9a133b70..3399e95629ba8542d6b672a8c527a8b39e7ac07a 100644
--- a/Source/platform/graphics/paint/ScrollDisplayItem.h
+++ b/Source/platform/graphics/paint/ScrollDisplayItem.h
@@ -21,12 +21,12 @@ public:
         ASSERT(isScrollType(type));
     }
 
-    virtual void replay(GraphicsContext&) override;
-    virtual void appendToWebDisplayItemList(WebDisplayItemList*) const override;
+    void replay(GraphicsContext&) override;
+    void appendToWebDisplayItemList(WebDisplayItemList*) const override;
 
 private:
 #ifndef NDEBUG
-    virtual void dumpPropertiesAsDebugString(WTF::StringBuilder&) const override final;
+    void dumpPropertiesAsDebugString(WTF::StringBuilder&) const final;
 #endif
 
     const IntSize m_currentOffset;
@@ -40,12 +40,12 @@ public:
         ASSERT(isEndScrollType(type));
     }
 
-    virtual void replay(GraphicsContext&) override;
-    virtual void appendToWebDisplayItemList(WebDisplayItemList*) const override;
+    void replay(GraphicsContext&) override;
+    void appendToWebDisplayItemList(WebDisplayItemList*) const override;
 
 private:
 #if ENABLE(ASSERT)
-    virtual bool isEndAndPairedWith(DisplayItem::Type otherType) const override final { return DisplayItem::isScrollType(otherType); }
+    bool isEndAndPairedWith(DisplayItem::Type otherType) const final { return DisplayItem::isScrollType(otherType); }
 #endif
 };