[glib] GContextSpecificGroup: detach sources

[Allison Ryan Lortie <desrt src gnome org>]

commit 62f320e6bb09b4e6454e6a49dc3a844b13b9cc34
Author: Allison Ryan Lortie <desrt desrt ca>
Date:   Tue Apr 26 10:39:42 2016 +0200

    GContextSpecificGroup: detach sources
    
    GContextSpecificGroup has been somewhat broken for a rather long time:
    when we remove the last reference on an object held in the group, we try
    to clean up the source, but fail to actually remove it from the
    mainloop.
    
    We will soon stop emitting signals on the source (due to it having been
    removed from the hash table) but any "in flight" signals will still be
    delivered on the source, which continues to exist.  This is a problem if
    the event is being delivered just as the object is being destroyed.
    
    This also means that we leave the source attached to the mainloop
    forever (and next time will create a new one)...
    
    This is demonstrated with the GtkAppChooser dialog which writes an
    update to the mimeapps.list file just as it is closing, triggering the
    app info monitor to fire just as it is being destroyed.
    
    Karl Tomlinson correctly analysed the problem and proposed this fix.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=762994

 gio/gcontextspecificgroup.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/gio/gcontextspecificgroup.c b/gio/gcontextspecificgroup.c
index b0eb279..211d765 100644
--- a/gio/gcontextspecificgroup.c
+++ b/gio/gcontextspecificgroup.c
@@ -234,6 +234,7 @@ g_context_specific_group_remove (GContextSpecificGroup *group,
 
   g_assert (css->instance == instance);
 
+  g_source_destroy ((GSource *) css);
   g_source_unref ((GSource *) css);
   g_main_context_unref (context);
 }