update UserDataManager

MediaBrowser.Server.Implementations/Library/UserDataManager.cs

@@ -170,23 +170,19 @@ namespace MediaBrowser.Server.Implementations.Library
                         return value;
                     }
                 }
+            }
 
             if (keys.Count > 0)
             {
-                    var key = keys[0];
-                    var cacheKey = GetCacheKey(userId, key);
-                    var userdata = new UserItemData
+                return new UserItemData
                 {
                     UserId = userId,
-                        Key = key
+                    Key = keys[0]
                 };
-                    _userData[cacheKey] = userdata;
-                    return userdata;
             }
 
             return null;
         }
-        }
 
         /// <summary>
         /// Gets the user data.