[totem] properties: Fix crash when properties are closed fast

[Bastien Nocera <hadess src gnome org>]

commit 57ceb48f4db464f785a084859c55ad20cbc639f5
Author: Bastien Nocera <hadess hadess net>
Date:   Thu Sep 21 20:04:31 2017 +0200

    properties: Fix crash when properties are closed fast
    
    Cancel the GstDiscoverer process when closing the window.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=787996

 src/totem-properties-view.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)
---
diff --git a/src/totem-properties-view.c b/src/totem-properties-view.c
index bf681c8..51c1334 100644
--- a/src/totem-properties-view.c
+++ b/src/totem-properties-view.c
@@ -345,7 +345,13 @@ totem_properties_view_finalize (GObject *object)
        props = TOTEM_PROPERTIES_VIEW (object);
 
        if (props->priv != NULL) {
-               g_clear_object (&props->priv->disco);
+               if (props->priv->disco) {
+                       g_signal_handlers_disconnect_by_func (props->priv->disco,
+                                                             discovered_cb,
+                                                             props);
+                       gst_discoverer_stop (props->priv->disco);
+                       g_clear_object (&props->priv->disco);
+               }
                g_clear_object (&props->priv->label);
                g_free (props->priv);
        }