Fix failing System.Text.Json test (dotnet/corefx#40439)

Commit migrated from https://github.com/dotnet/corefx/commit/cf5c1b0a7c3cf0087ae72fd0e1995a274cfefe27

diff --git a/src/libraries/System.Text.Json/tests/Serialization/CustomConverterTests.DerivedTypes.cs b/src/libraries/System.Text.Json/tests/Serialization/CustomConverterTests.DerivedTypes.cs
index 6f8b171..680d862 100644 (file)
--- a/src/libraries/System.Text.Json/tests/Serialization/CustomConverterTests.DerivedTypes.cs
+++ b/src/libraries/System.Text.Json/tests/Serialization/CustomConverterTests.DerivedTypes.cs
@@ -106,7 +106,7 @@ namespace System.Text.Json.Serialization.Tests
             };
 
             // Without converter, we throw on deserialize.
-            Assert.Throws<JsonException>(() => JsonSerializer.Deserialize<UnsupportedDerivedTypesWrapper_IEnumerable>(json));
+            Assert.Throws<NotSupportedException>(() => JsonSerializer.Deserialize<UnsupportedDerivedTypesWrapper_IEnumerable>(json));
             // Without converter, we serialize as is.
             Assert.Equal(@"{""IEnumerableWrapper"":[""1"",""2"",""3""]}", JsonSerializer.Serialize(wrapper));