Updates #15771

Change-Id: I5dad96bdca19d680dd00cbd17b72a03e43eb557e
Reviewed-on: https://go-review.googlesource.com/23283Reviewed-by: Tom Bergan <tombergan@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>