CiviMail should not display mailings with no recipient groups or mailings to an ACL'ed user

As outlined in CRM-2220 mailings are only displayed to a user with ACL permissions when taht user has permissions for ALL the include/exclude groups and all the include/exclude mailings.

However, if a draft mailing is saved with no groups or mailings, that draft is visible to all ACL'ed users. Likewise if a mailing is sent using the results of a search, that mailing will be visible to all users regardless of their ACL permissions.

As an organization that uses ACLs extensively, my expectation is that mailings without included/excluded groups or included/excluded mailings in the recipients field would NOT be visible to an ACL'ed user, unless that creator of that mailing is included in the group the logged in user has ACL permissions over.