When I upgrade from 2.40 to 2.50 I encounter this problem in the system log.

error CS1061: 'Nop.Web.Models.Catalog.ProductModel' does not contain a definition for 'DisplayProductAddedMessage' and no extension method 'DisplayProductAddedMessage' accepting a first argument of type 'Nop.Web.Models.Catalog.ProductModel' could be found (are you missing a using directive or an assembly reference?)

Anyone have any idea?