Move NotificationDelegate into message_center.

ui/message_center/message_center.h

Index: ui/message_center/message_center.h
diff --git a/ui/message_center/message_center.h b/ui/message_center/message_center.h
index d971a30b52e5b747ca439532d71890b81ed7deb7..d1142698f9b19b59f633fedaef8374a66af3ebe7 100644
--- a/ui/message_center/message_center.h
+++ b/ui/message_center/message_center.h
@@ -91,14 +91,14 @@ class MESSAGE_CENTER_EXPORT MessageCenter {
   // from the extension. Otherwise if |display_source| is provided, a menu item
   // showing the source and allowing notifications from that source to be
   // disabled will be shown. All actual disabling is handled by the Delegate.
-  virtual void AddNotification(
-      NotificationType type,
-      const std::string& id,
-      const string16& title,
-      const string16& message,
-      const string16& display_source,
-      const std::string& extension_id,
-      const base::DictionaryValue* optional_fields) = 0;
+  virtual void AddNotification(NotificationType type,
+                               const std::string& id,
+                               const string16& title,
+                               const string16& message,
+                               const string16& display_source,
+                               const std::string& extension_id,
+                               const base::DictionaryValue* optional_fields,
+                               NotificationDelegate* delegate) = 0;
 
   // Updates an existing notification with id = old_id and set its id to new_id.
   // |optional_fields| can be NULL in case of no updates on those fields.