Add VectorIconButton functionality to ImageButton.

ui/message_center/views/notification_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_NOTIFICATION_VIEW_H_
 #define UI_MESSAGE_CENTER_VIEWS_NOTIFICATION_VIEW_H_
 
 #include <vector>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "ui/message_center/message_center_export.h"
 #include "ui/message_center/views/message_view.h"
-#include "ui/views/controls/button/button.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/view_targeter_delegate.h"
 
 namespace views {
 class ImageView;
 class ProgressBar;
 }
 
 namespace message_center {
 
 class BoundedLabel;
 class NotificationButton;
 class ProportionalImageView;
 
 // View that displays all current types of notification (web, basic, image, and
 // list) except the custom notification. Future notification types may be
 // handled by other classes, in which case instances of those classes would be
 // returned by the Create() factory method below.
 class MESSAGE_CENTER_EXPORT NotificationView
     : public MessageView,
-      public views::ButtonListener,
+      public views::ImageButtonDelegate,
       public views::ViewTargeterDelegate {
  public:
   NotificationView(MessageCenterController* controller,
                    const Notification& notification);
   ~NotificationView() override;
 
   // Overridden from views::View:
   gfx::Size GetPreferredSize() const override;
   int GetHeightForWidth(int width) const override;
   void Layout() override;
@@ skipping 73 matching lines @@
   std::vector<views::View*> separators_;
   std::unique_ptr<views::ImageButton> close_button_ = nullptr;
   std::unique_ptr<views::ImageView> small_image_view_;
 
   DISALLOW_COPY_AND_ASSIGN(NotificationView);
 };
 
 }  // namespace message_center
 
 #endif  // UI_MESSAGE_CENTER_VIEWS_NOTIFICATION_VIEW_H_