Found by github.com/mvdan/unparam.

Change-Id: Iabcdfec2ae42c735aa23210b7183080d750682ca
Reviewed-on: https://go-review.googlesource.com/38030Reviewed-by: Peter Weinberger <pjw@google.com>
Run-TryBot: Peter Weinberger <pjw@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>