C++11 override style change for athena

athena/extensions/chrome/athena_extension_install_ui.cc

Index: athena/extensions/chrome/athena_extension_install_ui.cc
diff --git a/athena/extensions/chrome/athena_extension_install_ui.cc b/athena/extensions/chrome/athena_extension_install_ui.cc
index a4bfaa39e8156b8c6c763bb1322d7d0c70573584..583dfd5630fb7bc9a5b154bd23efba39893e91c4 100644
--- a/athena/extensions/chrome/athena_extension_install_ui.cc
+++ b/athena/extensions/chrome/athena_extension_install_ui.cc
@@ -25,12 +25,12 @@ class MessageDialogDelegate : public views::DialogDelegateView {
   explicit MessageDialogDelegate(const base::string16& message)
       : message_(message) {}
 
-  virtual ~MessageDialogDelegate() {}
+  ~MessageDialogDelegate() override {}
 
   // views::DialogDelegateView:
-  virtual base::string16 GetWindowTitle() const override { return message_; }
+  base::string16 GetWindowTitle() const override { return message_; }
 
-  virtual int GetDialogButtons() const override { return ui::DIALOG_BUTTON_OK; }
+  int GetDialogButtons() const override { return ui::DIALOG_BUTTON_OK; }
 
  private:
   base::string16 message_;