[gnome-calendar] month-view: Don't get weather info before having a date

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 21e748ac36dd5e82cdd3ed33aa7abfba3bc32151
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Thu Apr 25 16:35:37 2019 -0300

    month-view: Don't get weather info before having a date

 src/views/gcal-month-view.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/src/views/gcal-month-view.c b/src/views/gcal-month-view.c
index 706e0881..72168f49 100644
--- a/src/views/gcal-month-view.c
+++ b/src/views/gcal-month-view.c
@@ -876,6 +876,9 @@ get_weather_info_for_cell (GcalMonthView *self,
   GDate first;
   guint i;
 
+  if (!self->date)
+    return NULL;
+
   weather_service = gcal_context_get_weather_service (self->context);
   weather_infos = gcal_weather_service_get_weather_infos (weather_service);