Updates #18437

Change-Id: Iaa8a35d18eca8be24763dd151ad9e324ecbf7f7b
Reviewed-on: https://go-review.googlesource.com/34726
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>