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In response to #2122. 

I have one broken feature spec in `features/symbol_leak.feature:20` -- not quite sure how to fix it. 
Instead of calling `display_name` directly on the resource, you'd pass the resource to AA's [`display_name`](https://github.com/gregbell/active_admin/blob/27360996837146ebbbf3b3597049b1586542fbeb/lib/active_admin/view_helpers/display_helper.rb#L17).