Standardize usage of virtual/override/final specifiers.

ash/display/screen_position_controller.h

Index: ash/display/screen_position_controller.h
diff --git a/ash/display/screen_position_controller.h b/ash/display/screen_position_controller.h
index e1e8690b5a56539e8220103e0d93c6bae024b71a..fd288540ffef2866c5f6f853bc9ee5861f3409ec 100644
--- a/ash/display/screen_position_controller.h
+++ b/ash/display/screen_position_controller.h
@@ -13,18 +13,18 @@ namespace ash {
 class ScreenPositionController : public aura::client::ScreenPositionClient {
  public:
   ScreenPositionController() {}
-  virtual ~ScreenPositionController() {}
+  ~ScreenPositionController() override {}
 
   // aura::client::ScreenPositionClient overrides:
-  virtual void ConvertPointToScreen(const aura::Window* window,
-                                    gfx::Point* point) override;
-  virtual void ConvertPointFromScreen(const aura::Window* window,
-                                      gfx::Point* point) override;
-  virtual void ConvertHostPointToScreen(aura::Window* window,
-                                        gfx::Point* point) override;
-  virtual void SetBounds(aura::Window* window,
-                         const gfx::Rect& bounds,
-                         const gfx::Display& display) override;
+  void ConvertPointToScreen(const aura::Window* window,
+                            gfx::Point* point) override;
+  void ConvertPointFromScreen(const aura::Window* window,
+                              gfx::Point* point) override;
+  void ConvertHostPointToScreen(aura::Window* window,
+                                gfx::Point* point) override;
+  void SetBounds(aura::Window* window,
+                 const gfx::Rect& bounds,
+                 const gfx::Display& display) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ScreenPositionController);