Fixes golang/go#23121

Change-Id: I71495b82a573e9f492a52dde325522a6203c06eb
Reviewed-on: https://go-review.googlesource.com/83855Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>