This wasn't converted during CL 110875

Updates golang/go#25134

Change-Id: Iaa579e0c173d3e27cf9f7e20072752277089beb1
Reviewed-on: https://go-review.googlesource.com/c/139977
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>