user: Improve SetActiveWindow test, add SetForegroundWindow test, make them pass under Wine.
diff --git a/server/window.c b/server/window.c
index f2017ec..82d709d 100644
--- a/server/window.c
+++ b/server/window.c
@@ -110,7 +110,7 @@
 inline static struct window *get_window( user_handle_t handle )
 {
     struct window *ret = get_user_object( handle, USER_WINDOW );
-    if (!ret) set_error( STATUS_INVALID_HANDLE );
+    if (!ret) set_win32_error( ERROR_INVALID_WINDOW_HANDLE );
     return ret;
 }