use lambda form in acts_as_tree scope (#12499)

git-svn-id: http://svn.redmine.org/redmine/trunk@12487 e93f8b46-1217-0410-a6f0-8f06a7374b81
Rails4: replace deprecated Relation#update_all at db migrations

git-svn-id: http://svn.redmine.org/redmine/trunk@12488 e93f8b46-1217-0410-a6f0-8f06a7374b81