Passes toolstash-check -all.

Change-Id: Id389f8158cf33a3c0fcef373615b5351e7c74b5b
Reviewed-on: https://go-review.googlesource.com/38082
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>