There's more work to do.

Updates #17068

Change-Id: I4e16c0e8e9ac739e1fe266224c3769f6c5b2e070
Reviewed-on: https://go-review.googlesource.com/29076Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>