Client-side changes to support retry GU.

sync/engine/download.h

Index: sync/engine/download.h
diff --git a/sync/engine/download.h b/sync/engine/download.h
index 5bc08d434e1bb9a8b868cc694070a2c3f4d529a2..a2945a9665541b5acd981b64573694eaf3a90995 100644
--- a/sync/engine/download.h
+++ b/sync/engine/download.h
@@ -62,16 +62,18 @@ SYNC_EXPORT_PRIVATE void BuildDownloadUpdatesForConfigureImpl(
 
 // This function executes a single GetUpdate request and stores the response in
 // the session's status controller.  It constructs the type of request used for
-// periodic polling.
-SYNC_EXPORT_PRIVATE void BuildDownloadUpdatesForPoll(
+// periodic polling or retry.
+SYNC_EXPORT_PRIVATE void BuildSupplementDownloadUpdates(
     sessions::SyncSession* session,
     bool create_mobile_bookmarks_folder,
     ModelTypeSet request_types,
+    sync_pb::SyncEnums::GetUpdatesOrigin gu_origin,
     sync_pb::ClientToServerMessage* client_to_server_message);
 
 // Helper function.  Defined here for testing.
-SYNC_EXPORT_PRIVATE void BuildDownloadUpdatesForPollImpl(
+SYNC_EXPORT_PRIVATE void BuildSupplementDownloadUpdatesImpl(
     ModelTypeSet proto_request_types,
+    sync_pb::SyncEnums::GetUpdatesOrigin gu_origin,
     UpdateHandlerMap* update_handler_map,
     sync_pb::GetUpdatesMessage* get_updates);