Allow Safe Browsing backend to select downloads to upload.

chrome/browser/safe_browsing/download_feedback_service.h

Index: chrome/browser/safe_browsing/download_feedback_service.h
diff --git a/chrome/browser/safe_browsing/download_feedback_service.h b/chrome/browser/safe_browsing/download_feedback_service.h
index 474e4d80777f01e2549505834c546cc6235bcfa5..a963756f2437f242276194181dffb5e9e4b672b2 100644
--- a/chrome/browser/safe_browsing/download_feedback_service.h
+++ b/chrome/browser/safe_browsing/download_feedback_service.h
@@ -43,9 +43,12 @@ class DownloadFeedbackService {
   // Stores the request and response ping data from the download check, if the
   // check result and file size are eligible. This must be called after a
   // download has been flagged as malicious in order for the download to be
-  // enabled for uploading.
+  // enabled for uploading. Some "unknown" verdict files can be marked for
+  // upload by the server with |upload_requested| if it's needed for better

[Jialiu Lin, 2017/02/15 00:45:27]

nit: Do we need to mention "Unknown" verdict in the comment? This code does not
check whether the verdict is "unknown" or not. 

[Nathan Parker, 2017/02/15 01:38:04]

good point.  The plan is that the backend will only use this w/ unknown
verdicts, but I'm not enforcing it in the code.  Fixed the comment.

+  // classification.
   static void MaybeStorePingsForDownload(
       DownloadProtectionService::DownloadCheckResult result,
+      bool upload_requested,
       content::DownloadItem* download,
       const std::string& ping,
       const std::string& response);