Fixes #15689

Change-Id: I56d0103738cc35cd5bc5e77a0e0341c0dd55530e
Reviewed-on: https://go-review.googlesource.com/23440Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Nigel Tao <nigeltao@golang.org>