Include high-fidelity metadata about a download in incident reports.

chrome/common/safe_browsing/csd.proto

 // 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.
 //
 // Client side phishing and malware detection request and response
 // protocol buffers.  Those protocol messages should be kept in sync
 // with the server implementation.
 //
 // If you want to change this protocol definition or you have questions
 // regarding its format please contact chrome-anti-phishing@googlegroups.com.
@@ skipping 433 matching lines @@
 }
 
 message ClientIncidentResponse {
   optional bytes token = 1;
   optional bool download_requested = 2;
 
   message EnvironmentRequest { optional int32 dll_index = 1; }
 
   repeated EnvironmentRequest environment_requests = 3;
 }
+
+message DownloadMetadata {
+  optional uint32 download_id = 1;
+
+  optional ClientIncidentReport.DownloadDetails download = 2;
+}