rails/rails — pull request #12565 by stormsilver (2013-10-16 18:42:34+00:00)
Title: Allow unscope to work with `where.not`

Allows you to call `#unscope` on a relation with negative equality operators, i.e. `Arel::Nodes::NotIn` and `Arel::Nodes::NotEqual` that have been generated through the use of `where.not`.