Adds a small icon to notifications, and connects it to synced notifications.

chrome/browser/notifications/notification.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 CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_H_
 #define CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 107 matching lines @@
   // string-based notifications).
   GURL content_url_;
 
   // The URLs of the button images for a rich notification.
   GURL button_one_icon_url_;
   GURL button_two_icon_url_;
 
   // The URL of a large image to be displayed for a a rich notification.
   GURL image_url_;
 
+  // The URL of a small image to be displayed for a a rich notification.
+  GURL small_image_url_;

[robwu, 2014/05/22 21:04:16]

This is not used anywhere, shouldn't it be removed?

+
   // The user-supplied replace ID for the notification.
   base::string16 replace_id_;
 
   // A proxy object that allows access back to the JavaScript object that
   // represents the notification, for firing events.
   scoped_refptr<NotificationDelegate> delegate_;
 };
 
 #endif  // CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_H_