[Downloads] Use the initiating StoragePartition for resumption.

content/public/browser/download_manager.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.
 //
 // The DownloadManager object manages the process of downloading, including
 // updates to the history system and providing the information for displaying
 // the downloads view in the Destinations tab. There is one DownloadManager per
 // active browser context in Chrome.
 //
 // Download observers:
@@ skipping 128 matching lines @@
 
   // Called by the embedder, after creating the download manager, to let it know
   // about downloads from previous runs of the browser.
   virtual DownloadItem* CreateDownloadItem(
       const std::string& guid,
       uint32_t id,
       const base::FilePath& current_path,
       const base::FilePath& target_path,
       const std::vector<GURL>& url_chain,
       const GURL& referrer_url,
+      const GURL& site_instance_url,
       const GURL& tab_url,
       const GURL& tab_referrer_url,
       const std::string& mime_type,
       const std::string& original_mime_type,
       const base::Time& start_time,
       const base::Time& end_time,
       const std::string& etag,
       const std::string& last_modified,
       int64_t received_bytes,
       int64_t total_bytes,
@@ skipping 28 matching lines @@
   // if you need to keep track of a specific download. (http://crbug.com/593020)
   virtual DownloadItem* GetDownload(uint32_t id) = 0;
 
   // Get the download item for |guid|.
   virtual DownloadItem* GetDownloadByGuid(const std::string& guid) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_DOWNLOAD_MANAGER_H_