views: queue a redraw when the current date changes

This partially fixes bug #739550. The warning message is still being emmited.

src/gcal-month-view.c

@@ -263,6 +263,7 @@ gcal_month_view_set_property (GObject       *object,
                                      E_CAL_DATA_MODEL_SUBSCRIBER (object),
                                      range_start,
                                      range_end);
+        gtk_widget_queue_draw (GTK_WIDGET (object));
         break;
       }
     case PROP_MANAGER:

src/gcal-week-view.c

@@ -670,6 +670,7 @@ gcal_week_view_set_property (GObject       *object,
                                      E_CAL_DATA_MODEL_SUBSCRIBER (object),
                                      range_start,
                                      range_end);
+        gtk_widget_queue_draw (GTK_WIDGET (object));
         break;
       }
     case PROP_MANAGER:

src/gcal-year-view.c

@@ -255,6 +255,7 @@ gcal_year_view_set_property (GObject       *object,
                                      E_CAL_DATA_MODEL_SUBSCRIBER (object),
                                      range_start,
                                      range_end);
+        gtk_widget_queue_draw (GTK_WIDGET (object));
         break;
       }
     case PROP_MANAGER: