Updates #13994
Updates #16840

Change-Id: Ia3cad5c211e0c688a945ed6b6277c2552592774c
Reviewed-on: https://go-review.googlesource.com/29760
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>