Use a DownloadRequestHandle pointer in construction to allow mocking for tests.

content/browser/download/download_file_manager.cc

Index: content/browser/download/download_file_manager.cc
diff --git a/content/browser/download/download_file_manager.cc b/content/browser/download/download_file_manager.cc
index 829cab9574981a6798665d55d6629ae3db74f3a5..5c2774b7efbaab0325625957fab350dcff767821 100644
--- a/content/browser/download/download_file_manager.cc
+++ b/content/browser/download/download_file_manager.cc
@@ -64,7 +64,9 @@ void DownloadFileManager::CreateDownloadFile(
   scoped_ptr<DownloadCreateInfo> infop(info);
 
   scoped_ptr<DownloadFile>
-      download_file(new DownloadFile(info, request_handle, download_manager));
+      download_file(new DownloadFile(info,
+                                     new DownloadRequestHandle(request_handle),
+                                     download_manager));
   if (net::OK != download_file->Initialize(get_hash)) {
     request_handle.CancelRequest();
     return;