Changed how model mappers work for persistence objects so we don't have to statically associate the mapper.

src/Umbraco.Core/Models/Membership/User.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Runtime.Serialization;
 using Umbraco.Core.Models.EntityBase;
+using Umbraco.Core.Persistence.Mappers;
 
 namespace Umbraco.Core.Models.Membership
 {
@@ -15,6 +16,7 @@ namespace Umbraco.Core.Models.Membership
     /// </remarks>
     [Serializable]
     [DataContract(IsReference = true)]
+    [Mapper(typeof(UserMapper))]
     internal class User : UserProfile, IUser
     {
         private bool _hasIdentity;