Fixes #16116.

Change-Id: Ic3cb0b95382bb683368743bda49b4eb5fdcc35c0
Reviewed-on: https://go-review.googlesource.com/24286Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>