Made notification center notifications collapsed and expandable.

ui/message_center/views/message_popup_bubble.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_POPUP_BUBBLE_H_
 #define UI_MESSAGE_CENTER_VIEWS_MESSAGE_POPUP_BUBBLE_H_
 
 #include <map>
 #include <set>
 #include <string>
 
 #include "base/timer.h"
 #include "ui/message_center/message_center_export.h"
-#include "ui/message_center/notification_list.h"
 #include "ui/message_center/views/message_bubble_base.h"
 
 namespace message_center {
 
 class PopupBubbleContentsView;
 
 // Bubble for popup notifications.
 class MESSAGE_CENTER_EXPORT MessagePopupBubble : public MessageBubbleBase {
  public:
-  explicit MessagePopupBubble(NotificationList::Delegate* delegate);
+  explicit MessagePopupBubble(MessageCenter* message_center);
 
   virtual ~MessagePopupBubble();
 
-  // Overridden from MessageBubbleBase.
+  // Overridden from MessageBubbleBase:
   virtual views::TrayBubbleView::InitParams GetInitParams(
       views::TrayBubbleView::AnchorAlignment anchor_alignment) OVERRIDE;
   virtual void InitializeContents(views::TrayBubbleView* bubble_view) OVERRIDE;
   virtual void OnBubbleViewDestroyed() OVERRIDE;
   virtual void UpdateBubbleView() OVERRIDE;
   virtual void OnMouseEnteredView() OVERRIDE;
   virtual void OnMouseExitedView() OVERRIDE;
 
    size_t NumMessageViewsForTest() const;
 
  private:
    class AutocloseTimer;
 
   void OnAutoClose(const std::string& id);
 
   void DeleteTimer(const std::string& id);
 
   std::map<std::string, AutocloseTimer*> autoclose_timers_;
   PopupBubbleContentsView* contents_view_;
   std::set<std::string> popup_ids_;
 
   DISALLOW_COPY_AND_ASSIGN(MessagePopupBubble);
 };
 
 }  // namespace message_center
 
 #endif // UI_MESSAGE_CENTER_VIEWS_MESSAGE_POPUP_BUBBLE_H_