Use scoped_ptr<> to store ConfirmBubbleModel.

chrome/browser/ui/cocoa/confirm_bubble_controller.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_UI_COCOA_CONFIRM_BUBBLE_CONTROLLER_H_
 #define CHROME_BROWSER_UI_COCOA_CONFIRM_BUBBLE_CONTROLLER_H_
 #pragma once
 
 #import <Cocoa/Cocoa.h>
 
 #import "base/mac/cocoa_protocols.h"
+#include "base/memory/scoped_ptr.h"
 
 class ConfirmBubbleModel;
 
 // A view controller that manages a bubble view and becomes a proxy between
 // the view and the ConfirmBubbleModel object. This class is internally used
 // in ConfirmBubbleView::Show() and users do not have to change this class
 // directly.
 @interface ConfirmBubbleController :
     NSViewController<NSTextViewDelegate> {
  @private
   NSView* parent_;  // weak
   CGPoint origin_;
-  ConfirmBubbleModel* model_;  // weak
+  scoped_ptr<ConfirmBubbleModel> model_;
 }
 
-// Creates a ConfirmBubbleController object.
+// Creates a ConfirmBubbleController object. The ConfirmBubbleController
+// controller takes the ownership of the passed-in ConfirmBubbleModel.
 - (id)initWithParent:(NSView*)parent
               origin:(CGPoint)origin
                model:(ConfirmBubbleModel*)model;
 
 // Access to the properties of the ConfirmBubbleModel object. These functions
 // also converts C++ types returned by the ConfirmBubbleModel object to
 // Objective-C types.
 - (NSPoint)origin;
 - (NSString*)title;
 - (NSString*)messageText;
 - (NSString*)linkText;
 - (NSString*)okButtonText;
 - (NSString*)cancelButtonText;
 - (BOOL)hasOkButton;
 - (BOOL)hasCancelButton;
 - (NSImage*)icon;
 
 // Handle actions from from the ConfirmBubbleView objet.
 - (void)accept;
 - (void)cancel;
 - (void)linkClicked;
 
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_CONFIRM_BUBBLE_CONTROLLER_H_