Must have been missed in a previous CL.

Change-Id: I303736e82585be8d58b330235c76ed4b24a92952
Reviewed-on: https://go-review.googlesource.com/111259
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>