fix usages of WindowsUtils

This amends 661de9d74ee8e74dbe85a5c52563094f63ee03c0.

Change-Id: Ie8ed84ceb44046797b7be55536cdbebb62fa0b83
Reviewed-by: Jake Petroules <jake.petroules@petroules.com>
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>