Comment 2 for bug 966054

StacktraceTop:
 gtk_gc_key_hash (key=0x0) at /build/buildd/gtk+2.0-2.24.10/gtk/gtkgc.c:206
 g_hash_table_lookup (hash_table=0x7fbd94ed5120, key=0x0) at /build/buildd/glib2.0-2.32.0/./glib/ghash.c:1072
 g_cache_remove (cache=0x7fbd94e5e120, value=0x7fbd94f17950) at /build/buildd/glib2.0-2.32.0/./glib/deprecated/gcache.c:290
 gtk_style_real_unrealize (style=0x7fbd94e48200) at /build/buildd/gtk+2.0-2.24.10/gtk/gtkstyle.c:2115
 g_cclosure_new (callback_func=0x7fbd94ee55e0, user_data=0x0, destroy_data=0x17) at /build/buildd/glib2.0-2.32.0/./gobject/gclosure.c:923