Regenerated with go tip to get the generated code comment following the
convention (https://golang.org/s/generatedcode).

Change-Id: Ie1365ecfa532b940bf7cfc8579c4cbda71cf7f76
Reviewed-on: https://go-review.googlesource.com/118817
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>