Otherwise, when str is empty, an invalid parameter exception is raised.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=30244Signed-off-by: Rémi Bernon <rbernon@codeweavers.com>
Signed-off-by: Piotr Caban <piotr@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>