Eliminates an inconsistency between user functions and generated
functions.

Passes toolstash-check.

Change-Id: I946b511ca81d88a0024b5932cb50f3d8b9e808f4
Reviewed-on: https://go-review.googlesource.com/103863
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>