[Downloads] Rework how hashes are calculated for download files.

content/browser/download/download_item_factory.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 DownloadItemFactory is used to produce different DownloadItems.
 // It is separate from the DownloadManager to allow download manager
 // unit tests to control the items produced.
 
 #ifndef CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_ITEM_FACTORY_H_
 #define CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_ITEM_FACTORY_H_
@@ skipping 37 matching lines @@
       const std::vector<GURL>& url_chain,
       const GURL& 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,
+      const std::string& hash,
       DownloadItem::DownloadState state,
       DownloadDangerType danger_type,
       DownloadInterruptReason interrupt_reason,
       bool opened,
       const net::BoundNetLog& bound_net_log) = 0;
 
   virtual DownloadItemImpl* CreateActiveItem(
       DownloadItemImplDelegate* delegate,
       uint32_t download_id,
       const DownloadCreateInfo& info,
       const net::BoundNetLog& bound_net_log) = 0;
 
   virtual DownloadItemImpl* CreateSavePageItem(
       DownloadItemImplDelegate* delegate,
       uint32_t download_id,
       const base::FilePath& path,
       const GURL& url,
       const std::string& mime_type,
       scoped_ptr<DownloadRequestHandleInterface> request_handle,
       const net::BoundNetLog& bound_net_log) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_ITEM_FACTORY_H_