Standardize usage of virtual/override/final specifiers.

ui/views/examples/tree_view_example.h

Index: ui/views/examples/tree_view_example.h
diff --git a/ui/views/examples/tree_view_example.h b/ui/views/examples/tree_view_example.h
index 4678b2a775fd57d78b2dc269df8ce754b0ca25f0..9ef57603823a67e8e5a7d63fd06c0c9fbfc08b77 100644
--- a/ui/views/examples/tree_view_example.h
+++ b/ui/views/examples/tree_view_example.h
@@ -28,10 +28,10 @@ class VIEWS_EXAMPLES_EXPORT TreeViewExample
       public ui::SimpleMenuModel::Delegate {
  public:
   TreeViewExample();
-  virtual ~TreeViewExample();
+  ~TreeViewExample() override;
 
   // ExampleBase:
-  virtual void CreateExampleView(View* container) override;
+  void CreateExampleView(View* container) override;
 
  private:
   // IDs used by the context menu.
@@ -48,24 +48,23 @@ class VIEWS_EXAMPLES_EXPORT TreeViewExample
   bool IsCommandIdEnabled(int command_id);
 
   // ButtonListener:
-  virtual void ButtonPressed(Button* sender, const ui::Event& event) override;
+  void ButtonPressed(Button* sender, const ui::Event& event) override;
 
   // TreeViewController:
-  virtual void OnTreeViewSelectionChanged(TreeView* tree_view) override;
-  virtual bool CanEdit(TreeView* tree_view, ui::TreeModelNode* node) override;
+  void OnTreeViewSelectionChanged(TreeView* tree_view) override;
+  bool CanEdit(TreeView* tree_view, ui::TreeModelNode* node) override;
 
   // ContextMenuController:
-  virtual void ShowContextMenuForView(View* source,
-                                      const gfx::Point& point,
-                                      ui::MenuSourceType source_type) override;
+  void ShowContextMenuForView(View* source,
+                              const gfx::Point& point,
+                              ui::MenuSourceType source_type) override;
 
   // SimpleMenuModel::Delegate:
-  virtual bool IsCommandIdChecked(int command_id) const override;
-  virtual bool IsCommandIdEnabled(int command_id) const override;
-  virtual bool GetAcceleratorForCommandId(
-      int command_id,
-      ui::Accelerator* accelerator) override;
-  virtual void ExecuteCommand(int command_id, int event_flags) override;
+  bool IsCommandIdChecked(int command_id) const override;
+  bool IsCommandIdEnabled(int command_id) const override;
+  bool GetAcceleratorForCommandId(int command_id,
+                                  ui::Accelerator* accelerator) override;
+  void ExecuteCommand(int command_id, int event_flags) override;
 
   // The tree view to be tested.
   TreeView* tree_view_;