Remove JsonObjectSerilizer and have storage helpers requiere a serilizer

Author: Rosuavio

Microsoft.Toolkit.Uwp/Helpers/ObjectStorage/BaseObjectStorageHelper.cs

@@ -21,14 +21,13 @@ public abstract class BaseObjectStorageHelper : IObjectStorageHelper
         /// <summary>
         /// Initializes a new instance of the <see cref="BaseObjectStorageHelper"/> class,
         /// which can read and write data using the provided <see cref="IObjectSerializer"/>;
-        /// if none is provided, a default Json serializer will be used (based on <see cref="DataContractSerializer"/>).
-        /// In 6.1 and older the default Serializer was based on Newtonsoft.Json and the new default Serializer may behave differently.
+        /// In 6.1 and older the default Serializer was based on Newtonsoft.Json.
         /// To implement a <see cref="IObjectSerializer"/> based on Newtonsoft.Json or System.Text.Json see https://aka.ms/wct/storagehelper-migration
         /// </summary>
         /// <param name="objectSerializer">The serializer to use.</param>
-        public BaseObjectStorageHelper(IObjectSerializer objectSerializer = null)
+        public BaseObjectStorageHelper(IObjectSerializer objectSerializer)
         {
-            serializer = objectSerializer ?? new JsonObjectSerializer();
+            serializer = objectSerializer ?? throw new ArgumentNullException(nameof(objectSerializer));
         }
 
         /// <summary>

Microsoft.Toolkit.Uwp/Helpers/ObjectStorage/JsonObjectSerializer.cs

@@ -15,12 +15,11 @@ public class LocalObjectStorageHelper : BaseObjectStorageHelper
         /// <summary>
         /// Initializes a new instance of the <see cref="LocalObjectStorageHelper"/> class,
         /// which can read and write data using the provided <see cref="IObjectSerializer"/>;
-        /// if none is provided, a default Json serializer will be used (based on <see cref="DataContractSerializer"/>).
-        /// In 6.1 and older the default Serializer was based on Newtonsoft.Json and the new default Serializer may behave differently.
+        /// In 6.1 and older the default Serializer was based on Newtonsoft.Json.
         /// To implement a <see cref="IObjectSerializer"/> based on Newtonsoft.Json or System.Text.Json see https://aka.ms/wct/storagehelper-migration
         /// </summary>
         /// <param name="objectSerializer">The serializer to use.</param>
-        public LocalObjectStorageHelper(IObjectSerializer objectSerializer = null)
+        public LocalObjectStorageHelper(IObjectSerializer objectSerializer)
             : base(objectSerializer)
         {
             Settings = ApplicationData.Current.LocalSettings;

Microsoft.Toolkit.Uwp/Helpers/ObjectStorage/LocalObjectStorageHelper.cs

@@ -15,12 +15,11 @@ public class RoamingObjectStorageHelper : BaseObjectStorageHelper
         /// <summary>
         /// Initializes a new instance of the <see cref="RoamingObjectStorageHelper"/> class,
         /// which can read and write data using the provided <see cref="IObjectSerializer"/>;
-        /// if none is provided, a default Json serializer will be used (based on <see cref="DataContractSerializer"/>).
-        /// In 6.1 and older the default Serializer was based on Newtonsoft.Json and the new default Serializer may behave differently.
+        /// In 6.1 and older the default Serializer was based on Newtonsoft.Json.
         /// To implement a <see cref="IObjectSerializer"/> based on Newtonsoft.Json or System.Text.Json see https://aka.ms/wct/storagehelper-migration
         /// </summary>
         /// <param name="objectSerializer">The serializer to use.</param>
-        public RoamingObjectStorageHelper(IObjectSerializer objectSerializer = null)
+        public RoamingObjectStorageHelper(IObjectSerializer objectSerializer)
             : base(objectSerializer)
         {
             Settings = ApplicationData.Current.RoamingSettings;