Code review comment for lp:~larstiq/bzr-svn/filter_stacks_registry

Hi Wouter,

Thanks for the fix. We should still look for the old name too, as bzr-svn supports bzr 2.5 and bzr 2.6 (only 2.6 deprecates lazy_register_filter_stack_map). 2.5 doesn't have the new registry.