gio: Add names to idles and timeouts

This isn't too useful for some of the "return result in idle"
functions, but it's better than nothing.

https://bugzilla.gnome.org/show_bug.cgi?id=726872

gio/gactiongroupexporter.c

@@ -238,6 +238,7 @@ g_action_group_exporter_set_events (GActionGroupExporter *exporter,
       source = g_idle_source_new ();
       exporter->pending_source = source;
       g_source_set_callback (source, g_action_group_exporter_dispatch_events, exporter, NULL);
+      g_source_set_name (source, "[gio] g_action_group_exporter_dispatch_events");
       g_source_attach (source, exporter->context);
       g_source_unref (source);
     }