Fixed #15212 -- ensure that ModelAdmin.get_actions still returns a SortedDict if there are no actions.
Fixed #15212 -- ensure that ModelAdmin.get_actions still returns a SortedDict if there are no actions.

git-svn-id: 4f9f921b081c523744c7bf24d959a0db39629563@15393 bcc190cf-cafb-0310-a4f2-bffc1f526a37

jamespacileo/django-france,jamespacileo/django-france,skevy/django,disqus/django-old,disqus/django-old,jamespacileo/django-france,Instagram/django,Instagram/django,django-nonrel/django-nonrel,disqus/django-old,skevy/django,mitsuhiko/django,mitsuhiko/django,skevy/django,django-nonrel/django-nonrel,mitsuhiko/django,django-nonrel/django-nonrel,Instagram/django