BrowserContext should simply own DownloadManager

chrome/browser/download/chrome_download_manager_delegate.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_DOWNLOAD_CHROME_DOWNLOAD_MANAGER_DELEGATE_H_
 #define CHROME_BROWSER_DOWNLOAD_CHROME_DOWNLOAD_MANAGER_DELEGATE_H_
 
 #include "base/compiler_specific.h"
 #include "base/hash_tables.h"
 #include "base/memory/ref_counted.h"
@@ skipping 86 matching lines @@
   void ClearLastDownloadPath();
 
   DownloadPrefs* download_prefs() { return download_prefs_.get(); }
 
  protected:
   // So that test classes can inherit from this for override purposes.
   virtual ~ChromeDownloadManagerDelegate();
 
   // So that test classes that inherit from this for override purposes
   // can call back into the DownloadManager.
-  scoped_refptr<content::DownloadManager> download_manager_;
+  content::DownloadManager* download_manager_;
 
   virtual safe_browsing::DownloadProtectionService*
       GetDownloadProtectionService();
 
   // DownloadTargetDeterminerDelegate. Protected for testing.
   virtual void NotifyExtensions(
       content::DownloadItem* download,
       const base::FilePath& suggested_virtual_path,
       const NotifyExtensionsCallback& callback) OVERRIDE;
   virtual void ReserveVirtualPath(
@@ skipping 53 matching lines @@
   content::NotificationRegistrar registrar_;
 
   // The directory most recently chosen by the user in response to a Save As
   // dialog for a regular download.
   base::FilePath last_download_path_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeDownloadManagerDelegate);
 };
 
 #endif  // CHROME_BROWSER_DOWNLOAD_CHROME_DOWNLOAD_MANAGER_DELEGATE_H_