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

Source/core/dom/DocumentFragment.h

Index: Source/core/dom/DocumentFragment.h
diff --git a/Source/core/dom/DocumentFragment.h b/Source/core/dom/DocumentFragment.h
index 27ffd82938cb48b551c78fb952ecf04e73e774b0..de58ffc2689152920eb57f269aa29da70308cf83 100644
--- a/Source/core/dom/DocumentFragment.h
+++ b/Source/core/dom/DocumentFragment.h
@@ -38,17 +38,17 @@ public:
     void parseHTML(const String&, Element* contextElement, ParserContentPolicy = AllowScriptingContent);
     bool parseXML(const String&, Element* contextElement, ParserContentPolicy = AllowScriptingContent);
 
-    virtual bool canContainRangeEndPoint() const override final { return true; }
+    bool canContainRangeEndPoint() const final { return true; }
     virtual bool isTemplateContent() const { return false; }
 
 protected:
     DocumentFragment(Document*, ConstructionType = CreateContainer);
-    virtual String nodeName() const override final;
+    String nodeName() const final;
 
 private:
-    virtual NodeType nodeType() const override final;
-    virtual PassRefPtrWillBeRawPtr<Node> cloneNode(bool deep = true) override;
-    virtual bool childTypeAllowed(NodeType) const override;
+    NodeType nodeType() const final;
+    PassRefPtrWillBeRawPtr<Node> cloneNode(bool deep = true) override;
+    bool childTypeAllowed(NodeType) const override;
 
     bool isDocumentFragment() const = delete; // This will catch anyone doing an unnecessary check.
 };