Updates #19632.

Change-Id: I1411dd997c8c6a789d17d0dcc0bfbd2281447b16
Reviewed-on: https://go-review.googlesource.com/38401
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>