Fix virtual/override/final usage in Source/core/{fetch,loader,streams,xmlhttprequest}/.

Source/core/fetch/TextResource.h

Index: Source/core/fetch/TextResource.h
diff --git a/Source/core/fetch/TextResource.h b/Source/core/fetch/TextResource.h
index 9054e5cba7eb54384574ab0ef9be3ec58f2492c0..e106f9c37857fc47ded644c5cc3cbdc8078a415c 100644
--- a/Source/core/fetch/TextResource.h
+++ b/Source/core/fetch/TextResource.h
@@ -18,12 +18,12 @@ public:
     // call time.
     String decodedText() const;
 
-    virtual void setEncoding(const String&) override;
-    virtual String encoding() const override;
+    void setEncoding(const String&) override;
+    String encoding() const override;
 
 protected:
     TextResource(const ResourceRequest&, Type, const String& mimeType, const String& charset);
-    virtual ~TextResource();
+    ~TextResource() override;
 
 private:
     OwnPtr<TextResourceDecoder> m_decoder;