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

Source/wtf/FilePrintStream.h

Index: Source/wtf/FilePrintStream.h
diff --git a/Source/wtf/FilePrintStream.h b/Source/wtf/FilePrintStream.h
index db0b51f70c616d86c5a1012ea1ce62132e29a932..7e20d24dea22233c591a17a397938d4e924cd712 100644
--- a/Source/wtf/FilePrintStream.h
+++ b/Source/wtf/FilePrintStream.h
@@ -40,14 +40,14 @@ public:
     };
 
     FilePrintStream(FILE*, AdoptionMode = Adopt);
-    virtual ~FilePrintStream();
+    ~FilePrintStream() override;
 
     static PassOwnPtr<FilePrintStream> open(const char* filename, const char* mode);
 
     FILE* file() { return m_file; }
 
-    virtual void vprintf(const char* format, va_list) override WTF_ATTRIBUTE_PRINTF(2, 0);
-    virtual void flush() override;
+    void vprintf(const char* format, va_list) override WTF_ATTRIBUTE_PRINTF(2, 0);
+    void flush() override;
 
 private:
     FILE* m_file;