After Remove/Rename, the extra-records filewatcher retried with
context.Background and the default 15-minute backoff budget, so Close
could not stop Run. Cancel that retry when closeCh closes. If the file
is still missing after the budget, watch the parent directory so a later
recreate is seen.
Close the fsnotify watcher on NewExtraRecordsManager error paths after
NewWatcher succeeds.
Signed-off-by: Sebastien Tardif <sebtardif@ncf.ca>