Remove redundant code

Fixes golang/go#18053

Change-Id: Ic8a2b85819ce86e5ebf2cc6274c604fdb69a5495
Reviewed-on: https://go-review.googlesource.com/33612Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>