Added Obsolete attributes to old storage helper tests

Author: shweaver-MSFT

UnitTests/UnitTests.UWP/Helpers/JsonObjectSerializer.cs

@@ -13,6 +13,7 @@ namespace UnitTests.Helpers
     /// This is a Serializer which should mimic the previous functionality of 6.1.1 release of the Toolkit with Newtonsoft.Json.
     /// Based on <see cref="Microsoft.Toolkit.Helpers.Uwp.IObjectSerializer"/>.
     /// </summary>
+    [Obsolete]
     internal class JsonObjectSerializer : IObjectSerializer
     {
         public T Deserialize<T>(object value)

UnitTests/UnitTests.UWP/Helpers/SystemTextJsonSerializer.cs

@@ -12,6 +12,7 @@ namespace UnitTests.Helpers
     /// Example class of writing a new <see cref="IObjectSerializer"/> that uses System.Text.Json.
     /// Based on <see cref="Microsoft.Toolkit.Helpers.Uwp.IObjectSerializer"/>.
     /// </summary>
+    [Obsolete]
     internal class SystemTextJsonSerializer : IObjectSerializer
     {
         public T Deserialize<T>(object value) => JsonSerializer.Deserialize<T>(value as string);

UnitTests/UnitTests.UWP/Helpers/Test_StorageHelper.cs

@@ -14,8 +14,11 @@ namespace UnitTests.Helpers
     [TestClass]
     public class Test_StorageHelper
     {
+        [Obsolete]
         private readonly LocalObjectStorageHelper _localStorageHelperSystem = new LocalObjectStorageHelper(new SystemSerializer());
+        [Obsolete]
         private readonly LocalObjectStorageHelper _localStorageHelperJsonCompat = new LocalObjectStorageHelper(new JsonObjectSerializer());
+        [Obsolete]
         private readonly LocalObjectStorageHelper _localStorageHelperJsonNew = new LocalObjectStorageHelper(new SystemTextJsonSerializer());
 
         /// <summary>
@@ -33,6 +36,7 @@ public void Test_StorageHelper_CheckNewtonsoftVersion()
 
         [TestCategory("Helpers")]
         [TestMethod]
+        [Obsolete]
         public void Test_StorageHelper_LegacyIntTest()
         {
             string key = "LifeUniverseAndEverything";
@@ -53,6 +57,7 @@ public void Test_StorageHelper_LegacyIntTest()
         /// </summary>
         [TestCategory("Helpers")]
         [TestMethod]
+        [Obsolete]
         [ExpectedException(typeof(NotSupportedException))]
         public void Test_StorageHelper_LegacyDateTestFailure()
         {
@@ -72,6 +77,7 @@ public void Test_StorageHelper_LegacyDateTestFailure()
         /// </summary>
         [TestCategory("Helpers")]
         [TestMethod]
+        [Obsolete]
         public void Test_StorageHelper_DateTestFailure()
         {
             Exception expectedException = null;
@@ -92,6 +98,7 @@ public void Test_StorageHelper_DateTestFailure()
 
         [TestCategory("Helpers")]
         [TestMethod]
+        [Obsolete]
         public void Test_StorageHelper_LegacyInternalClassTest()
         {
             string key = "Contact";
@@ -111,6 +118,7 @@ public void Test_StorageHelper_LegacyInternalClassTest()
 
         [TestCategory("Helpers")]
         [TestMethod]
+        [Obsolete]
         public void Test_StorageHelper_LegacyPublicClassTest()
         {
             string key = "Contact";
@@ -131,6 +139,7 @@ public void Test_StorageHelper_LegacyPublicClassTest()
 
         [TestCategory("Helpers")]
         [TestMethod]
+        [Obsolete]
         public void Test_StorageHelper_IntTest()
         {
             string key = "NewLifeUniverseAndEverything";
@@ -147,6 +156,7 @@ public void Test_StorageHelper_IntTest()
 
         [TestCategory("Helpers")]
         [TestMethod]
+        [Obsolete]
         public void Test_StorageHelper_NewDateTest()
         {
             string key = "NewChristmasDay";
@@ -163,6 +173,7 @@ public void Test_StorageHelper_NewDateTest()
 
         [TestCategory("Helpers")]
         [TestMethod]
+        [Obsolete]
         public void Test_StorageHelper_NewPersonTest()
         {
             string key = "Contact";