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

Source/core/html/HTMLTemplateElement.h

Index: Source/core/html/HTMLTemplateElement.h
diff --git a/Source/core/html/HTMLTemplateElement.h b/Source/core/html/HTMLTemplateElement.h
index a9e6ae5ae6b3f689aa1802bf747f341b0da5560c..2185690e77c2ac7d4bbed3e3bda29d3594ede026 100644
--- a/Source/core/html/HTMLTemplateElement.h
+++ b/Source/core/html/HTMLTemplateElement.h
@@ -42,14 +42,14 @@ class HTMLTemplateElement final : public HTMLElement {
     DEFINE_WRAPPERTYPEINFO();
 public:
     DECLARE_NODE_FACTORY(HTMLTemplateElement);
-    virtual ~HTMLTemplateElement();
+    ~HTMLTemplateElement() override;
     DECLARE_VIRTUAL_TRACE();
 
     DocumentFragment* content() const;
 
 private:
-    virtual PassRefPtrWillBeRawPtr<Node> cloneNode(bool deep = true) override;
-    virtual void didMoveToNewDocument(Document& oldDocument) override;
+    PassRefPtrWillBeRawPtr<Node> cloneNode(bool deep = true) override;
+    void didMoveToNewDocument(Document& oldDocument) override;
 
     explicit HTMLTemplateElement(Document&);