cases: fix icu breakage

wasn’t caught as it requires a build tag to compile.

Change-Id: I760a02e85cd512e8f089382ebcb87b0d94d0bd07
Reviewed-on: https://go-review.googlesource.com/29182
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
1 file changed