Per https://groups.google.com/forum/#!topic/golang-dev/javNmryAh0I

Change-Id: I08d7cbc94da4fc61c848f3dbee4637bf8fcfeb01
Reviewed-on: https://go-review.googlesource.com/18630Reviewed-by: Alan Donovan <adonovan@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Chris Broadfoot <cbro@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>