[glibmm] Dispatcher: Actually delete thread_specific_instance_.

[Murray Cumming <murrayc src gnome org>]

commit cc3e499b41cd66fd84a387c0612d2a5cd1d59277
Author: Murray Cumming <murrayc murrayc com>
Date:   Sat Nov 28 13:32:29 2015 +0100

    Dispatcher: Actually delete thread_specific_instance_.
    
    As suggested by Kjell here:
    https://bugzilla.gnome.org/show_bug.cgi?id=757674#c17

 glib/glibmm/dispatcher.cc |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/glib/glibmm/dispatcher.cc b/glib/glibmm/dispatcher.cc
index 3137270..9452245 100644
--- a/glib/glibmm/dispatcher.cc
+++ b/glib/glibmm/dispatcher.cc
@@ -319,7 +319,7 @@ void DispatchNotifier::unreference_instance(
   {
     g_return_if_fail(instance->ref_count_ == 0); // could be < 0 if messed up
 
-    // This causes deletion of the notifier object.
+    delete thread_specific_instance_;
     thread_specific_instance_ = nullptr;
   }
 }