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

Source/modules/gamepad/GamepadDispatcher.h

Index: Source/modules/gamepad/GamepadDispatcher.h
diff --git a/Source/modules/gamepad/GamepadDispatcher.h b/Source/modules/gamepad/GamepadDispatcher.h
index d77f6c23a39b6369dba72db649575f5204e26c3a..43cfc3b7500b851a17a764adcb22764bd11af158 100644
--- a/Source/modules/gamepad/GamepadDispatcher.h
+++ b/Source/modules/gamepad/GamepadDispatcher.h
@@ -18,7 +18,7 @@ class GamepadDispatcher final : public GarbageCollectedFinalized<GamepadDispatch
     USING_GARBAGE_COLLECTED_MIXIN(GamepadDispatcher);
 public:
     static GamepadDispatcher& instance();
-    virtual ~GamepadDispatcher();
+    ~GamepadDispatcher() override;
 
     void sampleGamepads(WebGamepads&);
 
@@ -35,12 +35,12 @@ private:
     GamepadDispatcher();
 
     // WebGamepadListener
-    virtual void didConnectGamepad(unsigned index, const WebGamepad&) override;
-    virtual void didDisconnectGamepad(unsigned index, const WebGamepad&) override;
+    void didConnectGamepad(unsigned index, const WebGamepad&) override;
+    void didDisconnectGamepad(unsigned index, const WebGamepad&) override;
 
     // PlatformEventDispatcher
-    virtual void startListening() override;
-    virtual void stopListening() override;
+    void startListening() override;
+    void stopListening() override;
 
     void dispatchDidConnectOrDisconnectGamepad(unsigned index, const WebGamepad&, bool connected);