[evolution-data-server] M!8 - [CalDAV] Invert success value of schedule outbox free_busy

[Milan Crha <mcrha src gnome org>]

commit d39396e9a38e3830c2292a61f7eb276342de2849
Author: Jamie McClymont <jamiemcclymont catalyst net nz>
Date:   Wed Dec 12 09:07:43 2018 +0100

    M!8 - [CalDAV] Invert success value of schedule outbox free_busy
    
    Closes https://gitlab.gnome.org/GNOME/evolution-data-server/merge_requests/8

 src/calendar/backends/caldav/e-cal-backend-caldav.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/calendar/backends/caldav/e-cal-backend-caldav.c 
b/src/calendar/backends/caldav/e-cal-backend-caldav.c
index d38d0af82..f514ade73 100644
--- a/src/calendar/backends/caldav/e-cal-backend-caldav.c
+++ b/src/calendar/backends/caldav/e-cal-backend-caldav.c
@@ -1859,7 +1859,7 @@ ecb_caldav_get_free_busy_from_schedule_outbox_sync (ECalBackendCalDAV *cbdav,
        if (local_error)
                g_propagate_error (error, local_error);
 
-       return local_error != NULL;
+       return !local_error;
 }
 
 static gboolean