Fixed 45-degree layout for axis labels, too.

Change-Id: I9764e281aeee0a439fa9eec1e3b0df840221b72f
Reviewed-on: https://gerrit.libreoffice.org/18889Reviewed-by: Jan Holesovsky <kendy@collabora.com>
Tested-by: Jan Holesovsky <kendy@collabora.com>