While we're here, remove a bit of dead code.

Change-Id: I1344bb41e5d368825ca5748189382f9e7023c59a
Reviewed-on: https://go-review.googlesource.com/20596
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>