Update {virtual,override,final} to follow C++11 style in ui.

ui/chromeos/network/network_list.h

Index: ui/chromeos/network/network_list.h
diff --git a/ui/chromeos/network/network_list.h b/ui/chromeos/network/network_list.h
index 1d4632d7ed15df955b963a0372499bf47f7722e5..24b19922e043282fb374fc9f5c92deb2934aaf3c 100644
--- a/ui/chromeos/network/network_list.h
+++ b/ui/chromeos/network/network_list.h
@@ -30,7 +30,7 @@ class UI_CHROMEOS_EXPORT NetworkListView
     : public network_icon::AnimationObserver {
  public:
   explicit NetworkListView(NetworkListDelegate* delegate);
-  virtual ~NetworkListView();
+  ~NetworkListView() override;
 
   void UpdateNetworkList();
 
@@ -56,7 +56,7 @@ class UI_CHROMEOS_EXPORT NetworkListView
   bool UpdateInfoLabel(int message_id, int index, views::Label** label);
 
   // network_icon::AnimationObserver:
-  virtual void NetworkIconChanged() override;
+  void NetworkIconChanged() override;
 
   NetworkListDelegate* delegate_;
   views::View* content_;