CL generated mechanically with github.com/mdempsky/unconvert.

Change-Id: I22eea0b991462dd00f3fa28073a8b886e19bc068
Reviewed-on: https://go-review.googlesource.com/100095
Run-TryBot: Kunpei Sakai <namusyaka@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>