[libglnx] Backport g_autoptr support for GCancellable

[Matthew Barnes <mbarnes src gnome org>]

commit c7da81208df4053774cb4b38adff8863ca0838f5
Author: Matthew Barnes <mbarnes redhat com>
Date:   Fri Nov 6 09:57:30 2015 -0500

    Backport g_autoptr support for GCancellable

 glnx-backport-autocleanups.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/glnx-backport-autocleanups.h b/glnx-backport-autocleanups.h
index f2bc483..271f5af 100644
--- a/glnx-backport-autocleanups.h
+++ b/glnx-backport-autocleanups.h
@@ -88,6 +88,7 @@ G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(GVariantDict, g_variant_dict_clear)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GVariantType, g_variant_type_free)
 
 /* Add GObject-based types add needed. */
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(GCancellable, g_object_unref)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GConverter, g_object_unref)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GConverterOutputStream, g_object_unref)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GDataInputStream, g_object_unref)