Cocoa does this automatically for non-owned windows and informs the back end
via a different mechanism (WINDOW_BROUGHT_FORWARD).  However, for owned windows
(child windows in Cocoa parlance), Cocoa does not change their z-order relative
to the owner (parent) or sibling owned windows when clicked.  So, we have to
move the window in user32's z-order so that it gets moved appropriately on
screen in response.
Signed-off-by: Ken Thomases <ken@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>