Adjust behavior of control buttons of notifications.

ui/message_center/views/message_view.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_MESSAGE_CENTER_VIEWS_MESSAGE_VIEW_H_
 #define UI_MESSAGE_CENTER_VIEWS_MESSAGE_VIEW_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 35 matching lines @@
 
   // Returns the insets for the shadow it will have for rich notification.
   static gfx::Insets GetShadowInsets();
 
   // Creates a shadow around the notification.
   void CreateShadowBorder();
 
   virtual bool IsCloseButtonFocused() const = 0;
   virtual void RequestFocusOnCloseButton() = 0;
   virtual bool IsPinned() const = 0;
+  virtual void UpdateControlButtonsVisibility() = 0;
 
   // Overridden from views::View:
   void GetAccessibleNodeData(ui::AXNodeData* node_data) override;
   bool OnMousePressed(const ui::MouseEvent& event) override;
   bool OnKeyPressed(const ui::KeyEvent& event) override;
   bool OnKeyReleased(const ui::KeyEvent& event) override;
   void OnPaint(gfx::Canvas* canvas) override;
   void OnFocus() override;
   void OnBlur() override;
   void Layout() override;
@@ skipping 39 matching lines @@
   base::string16 display_source_;
 
   std::unique_ptr<views::Painter> focus_painter_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageView);
 };
 
 }  // namespace message_center
 
 #endif // UI_MESSAGE_CENTER_VIEWS_MESSAGE_VIEW_H_