Standardize usage of virtual/override/final specifiers.

ui/views/controls/native/native_view_host_aura_unittest.cc

Index: ui/views/controls/native/native_view_host_aura_unittest.cc
diff --git a/ui/views/controls/native/native_view_host_aura_unittest.cc b/ui/views/controls/native/native_view_host_aura_unittest.cc
index 1a40ab76087120ac64593bb5a79b03f728c9930b..7f14bd47460b989867198f245bd8784558482e56 100644
--- a/ui/views/controls/native/native_view_host_aura_unittest.cc
+++ b/ui/views/controls/native/native_view_host_aura_unittest.cc
@@ -39,13 +39,12 @@ class NativeViewHostWindowObserver : public aura::WindowObserver {
   };
 
   NativeViewHostWindowObserver() {}
-  virtual ~NativeViewHostWindowObserver() {}
+  ~NativeViewHostWindowObserver() override {}
 
   const std::vector<EventDetails>& events() const { return events_; }
 
   // aura::WindowObserver overrides
-  virtual void OnWindowVisibilityChanged(aura::Window* window,
-                                         bool visible) override {
+  void OnWindowVisibilityChanged(aura::Window* window, bool visible) override {
     EventDetails event;
     event.type = visible ? EVENT_SHOWN : EVENT_HIDDEN;
     event.window = window;
@@ -57,9 +56,9 @@ class NativeViewHostWindowObserver : public aura::WindowObserver {
       events_.push_back(event);
   }
 
-  virtual void OnWindowBoundsChanged(aura::Window* window,
-                                     const gfx::Rect& old_bounds,
-                                     const gfx::Rect& new_bounds) override {
+  void OnWindowBoundsChanged(aura::Window* window,
+                             const gfx::Rect& old_bounds,
+                             const gfx::Rect& new_bounds) override {
     EventDetails event;
     event.type = EVENT_BOUNDS_CHANGED;
     event.window = window;