Add support to sha256 hash the downloaded file....

chrome/browser/download/download_file.cc

Index: chrome/browser/download/download_file.cc
===================================================================
--- chrome/browser/download/download_file.cc	(revision 70630)
+++ chrome/browser/download/download_file.cc	(working copy)
@@ -14,18 +14,19 @@
 #include "chrome/browser/history/download_create_info.h"
 
 DownloadFile::DownloadFile(const DownloadCreateInfo* info,
-                           DownloadManager* download_manager)
+                           DownloadManager* download_manager,
+                           bool calculate_hash)
     : BaseFile(info->save_info.file_path,
                info->url,
                info->referrer_url,
                info->received_bytes,
-               info->save_info.file_stream),
+               info->save_info.file_stream,
+               calculate_hash),
       id_(info->download_id),
       child_id_(info->child_id),
       request_id_(info->request_id),
       download_manager_(download_manager) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
-
 }
 
 DownloadFile::~DownloadFile() {