window: remove queued event on finalize

When the user removes an event, we first hide it and,
after a timeout, we remove it. The problem is that if
the user closes the window before the timeout is fired,
the event never gets deleted.

Fix that by deleting the event on finalize if there's
any event queued.

https://bugzilla.gnome.org/show_bug.cgi?id=762284

src/gcal-window.c

@@ -1390,6 +1390,13 @@ gcal_window_finalize (GObject *object)
       window->save_geometry_timeout_id = 0;
     }
 
+  /* If we have a queued event to delete, remove it now */
+  if (window->event_to_delete)
+    {
+      gcal_manager_remove_event (window->manager, window->event_to_delete);
+      g_clear_object (&window->event_to_delete);
+    }
+
   g_clear_object (&window->manager);
   g_clear_object (&window->views_switcher);