Fixes #11945.
Fixes #17446.

Change-Id: Ic674f6ebc0533ab0f97c650689125994941b72e1
Reviewed-on: https://go-review.googlesource.com/45081
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>