[gnome-calendar/mcatanzaro/rbz-1509551-gnome-3-32] Try to fix a crash in update_default_calendar_row()

[Michael Catanzaro <mcatanzaro src gnome org>]

commit c61ea47874ea92c30b04771c984a3cc4e9e1493b
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Tue Jul 2 12:16:43 2019 -0500

    Try to fix a crash in update_default_calendar_row()
    
    This function is crashing in 3.32 because the manager object is invalid.
    I think there are two related bugs:
    
    First, it looks like gcal_quick_add_popover_set_property() is failing to
    disconnect its signals from the old GcalManager before setting the new
    one. In one backtrace, I see the GcalManager emitting the signal is
    different than the GcalQuickAddPopover's current manager, which is
    surely unintended.
    
    But that shouldn't be enough to crash on its own, since the
    GcalQuickAddPopover should still have a valid manager, even if not the
    intended one. So I suspect the GcalQuickAddPopover itself is invalid at
    this point. (The crash occured for me after adding an event, so it was
    probably just destroyed.) GcalQuickAddPopover is not disconnecting these
    signals in dispose, which is unsafe. We can avoid the need to do so by
    using g_signal_connect_object().
    
    Hopefully fixes #416 for the 3.32 branch.
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1509551

 src/gcal-quick-add-popover.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)
---
diff --git a/src/gcal-quick-add-popover.c b/src/gcal-quick-add-popover.c
index 59567a62..30b9dc19 100644
--- a/src/gcal-quick-add-popover.c
+++ b/src/gcal-quick-add-popover.c
@@ -778,11 +778,16 @@ gcal_quick_add_popover_set_property (GObject      *object,
       break;
 
     case PROP_MANAGER:
-      if (g_set_object (&self->manager, g_value_get_object (value)))
+      if (self->manager != g_value_get_object (value))
         {
           GcalManager *manager;
           GList *sources, *l;
 
+          if (self->manager != NULL)
+            g_signal_handlers_disconnect_by_data (self->manager, self);
+
+          g_set_object (&self->manager, g_value_get_object (value));
+
           /* Add currently leaded sources */
           manager = self->manager;
           sources = gcal_manager_get_sources_connected (manager);
@@ -793,10 +798,10 @@ gcal_quick_add_popover_set_property (GObject      *object,
           g_list_free (sources);
 
           /* Connect to the manager signals and keep the list updates */
-          g_signal_connect (manager, "source-added", G_CALLBACK (on_source_added), self);
-          g_signal_connect (manager, "source-changed", G_CALLBACK (on_source_changed), self);
-          g_signal_connect (manager, "source-removed", G_CALLBACK (on_source_removed), self);
-          g_signal_connect_swapped (manager, "notify::default-calendar", G_CALLBACK 
(update_default_calendar_row), self);
+          g_signal_connect_object (manager, "source-added", G_CALLBACK (on_source_added), self, 0);
+          g_signal_connect_object (manager, "source-changed", G_CALLBACK (on_source_changed), self, 0);
+          g_signal_connect_object (manager, "source-removed", G_CALLBACK (on_source_removed), self, 0);
+          g_signal_connect_object (manager, "notify::default-calendar", G_CALLBACK 
(update_default_calendar_row), self, G_CONNECT_SWAPPED);
 
           g_object_notify (G_OBJECT (self), "manager");
         }