Clean up dead code

src/Microsoft.Extensions.DependencyModel/JsonTextReaderExtensions.cs

@@ -1,77 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved.
-// Licensed under the MIT license. See LICENSE file in the project root for full license information.
-
-using System;
-using System.Collections.Generic;
-using Newtonsoft.Json;
-
-namespace Microsoft.Extensions.DependencyModel
-{
-    internal static class JsonTextReaderExtensions
-    {
-        internal static bool TryReadStringProperty(this JsonTextReader reader, out string name, out string value)
-        {
-            name = null;
-            value = null;
-            if (reader.Read() && reader.TokenType == JsonToken.PropertyName)
-            {
-                name = (string)reader.Value;
-                value = reader.ReadAsString();
-                return true;
-            }
-
-            return false;
-        }
-
-        internal static void ReadStartObject(this JsonTextReader reader)
-        {
-            reader.Read();
-            CheckStartObject(reader);
-        }
-
-        internal static void CheckStartObject(this JsonTextReader reader)
-        {
-            if (reader.TokenType != JsonToken.StartObject)
-            {
-                throw CreateUnexpectedException(reader, "{");
-            }
-        }
-
-        internal static void CheckEndObject(this JsonTextReader reader)
-        {
-            if (reader.TokenType != JsonToken.EndObject)
-            {
-                throw CreateUnexpectedException(reader, "}");
-            }
-        }
-
-        internal static string[] ReadStringArray(this JsonTextReader reader)
-        {
-            reader.Read();
-            if (reader.TokenType != JsonToken.StartArray)
-            {
-                throw CreateUnexpectedException(reader,"[");
-            }
-
-            var items = new List<string>();
-
-            while (reader.Read() && reader.TokenType == JsonToken.String)
-            {
-                items.Add((string)reader.Value);
-            }
-
-            if (reader.TokenType != JsonToken.EndArray)
-            {
-                throw CreateUnexpectedException(reader, "]");
-            }
-
-            return items.ToArray();
-        }
-
-        internal static Exception CreateUnexpectedException(JsonTextReader reader, string expected)
-        {
-            return new FormatException($"Unexpected character encountered, excepted '{expected}' " +
-                                       $"at line {reader.LineNumber} position {reader.LinePosition} path {reader.Path}");
-        }
-    }
-}