fixes #762 - Marking unwatched doesn't update display

MediaBrowser.Controller/Entities/IHasUserData.cs

@@ -1,4 +1,6 @@
-
+using MediaBrowser.Model.Dto;
+using System;
+
 namespace MediaBrowser.Controller.Entities
 {
     /// <summary>
@@ -6,10 +8,24 @@ namespace MediaBrowser.Controller.Entities
     /// </summary>
     public interface IHasUserData
     {
+        /// <summary>
+        /// Gets or sets the identifier.
+        /// </summary>
+        /// <value>The identifier.</value>
+        Guid Id { get; set; }
+
         /// <summary>
         /// Gets the user data key.
         /// </summary>
         /// <returns>System.String.</returns>
         string GetUserDataKey();
+
+        /// <summary>
+        /// Fills the user data dto values.
+        /// </summary>
+        /// <param name="dto">The dto.</param>
+        /// <param name="userData">The user data.</param>
+        /// <param name="user">The user.</param>
+        void FillUserDataDtoValues(UserItemDataDto dto, UserItemData userData, User user);
     }
 }