The function was documented for use with a NULL scope, but it actually
crashes since callbacks are not available for NULL scopes. git master
is unaffected, but the GTK+ protocol dialog in 2.4 and 2.6 do crash.
Bug: 14349
Change-Id: I54350e112192394797cf85eaac4f30194178d7c4
Fixes: v2.3.0rc0-2597-gb7d6cca4ae ("Add wmem_tree_destroy")
Reviewed-on: https://code.wireshark.org/review/30126
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>