Handle the case where IAttachmentExecute::Save() deletes a downloaded file.

net/base/net_log_event_type_list.h

Index: net/base/net_log_event_type_list.h
diff --git a/net/base/net_log_event_type_list.h b/net/base/net_log_event_type_list.h
index 8fea0d50479946c4e4907c3f838a528d74832925..95f95ab957d8d7dd53b4223f66f052a6ad934e20 100644
--- a/net/base/net_log_event_type_list.h
+++ b/net/base/net_log_event_type_list.h
@@ -1651,6 +1651,10 @@ EVENT_TYPE(DOWNLOAD_FILE_ERROR)
 
 // This event is created when a download file is annotating with source
 // information (for Mark Of The Web and anti-virus integration).
+//   {
+//     "os_error": <OS specific error code>,
+//     "net_error": <net::Error code>
+//   }
 EVENT_TYPE(DOWNLOAD_FILE_ANNOTATED)
 
 // ------------------------------------------------------------------------