Fix ifdefs for nullability attributes

Author: captainsafia

src/Shared/ThrowHelpers/ArgumentNullThrowHelper.cs

@@ -14,7 +14,11 @@ internal static partial class ArgumentNullThrowHelper
     /// <summary>Throws an <see cref="ArgumentNullException"/> if <paramref name="argument"/> is null.</summary>
     /// <param name="argument">The reference type argument to validate as non-null.</param>
     /// <param name="paramName">The name of the parameter with which <paramref name="argument"/> corresponds.</param>
-    public static void ThrowIfNull([NotNull] object? argument, [CallerArgumentExpression("argument")] string? paramName = null)
+    public static void ThrowIfNull(
+#if INTERNAL_NULLABLE_ATTRIBUTES || NETSTANDARD2_1_OR_GREATER || NET5_0_OR_GREATER
+        [NotNull]
+#endif
+        object? argument, [CallerArgumentExpression("argument")] string? paramName = null)
     {
 #if !NET7_0_OR_GREATER || NETSTANDARD || NETFRAMEWORK
         if (argument is null)
@@ -27,7 +31,7 @@ public static void ThrowIfNull([NotNull] object? argument, [CallerArgumentExpres
     }
 
 #if !NET7_0_OR_GREATER || NETSTANDARD || NETFRAMEWORK
-#if !NETFRAMEWORK
+#if INTERNAL_NULLABLE_ATTRIBUTES || NETSTANDARD2_1_OR_GREATER || NET5_0_OR_GREATER
     [DoesNotReturn]
 #endif
     internal static void Throw(string? paramName) =>

src/Shared/ThrowHelpers/ArgumentThrowHelper.cs

@@ -19,7 +19,7 @@ internal static partial class ArgumentThrowHelper
     /// <param name="argument">The reference type argument to validate as neither null nor empty.</param>
     /// <param name="paramName">The name of the parameter with which <paramref name="argument"/> corresponds.</param>
     public static void ThrowIfNullOrEmpty(
-#if !NETFRAMEWORK
+#if INTERNAL_NULLABLE_ATTRIBUTES || NETSTANDARD2_1_OR_GREATER || NET5_0_OR_GREATER
         [NotNull]
 #endif
         string? argument, [CallerArgumentExpression("argument")] string? paramName = null)
@@ -36,7 +36,7 @@ public static void ThrowIfNullOrEmpty(
     }
 
 #if !NET7_0_OR_GREATER || NETSTANDARD || NETFRAMEWORK
-#if !NETFRAMEWORK
+#if INTERNAL_NULLABLE_ATTRIBUTES || NETSTANDARD2_1_OR_GREATER || NET5_0_OR_GREATER
     [DoesNotReturn]
 #endif
     internal static void Throw(string? paramName) =>

src/SiteExtensions/Microsoft.Web.Xdt.Extensions/src/Microsoft.Web.Xdt.Extensions.csproj

@@ -17,6 +17,7 @@
 
   <ItemGroup>
     <Compile Include="$(SharedSourceRoot)ThrowHelpers\ArgumentThrowHelper.cs" LinkBase="Shared" />
+    <Compile Include="$(SharedSourceRoot)ThrowHelpers\ArgumentNullThrowHelper.cs" LinkBase="Shared" />
     <Compile Include="$(SharedSourceRoot)CallerArgument\CallerArgumentExpressionAttribute.cs" LinkBase="Shared" />
   </ItemGroup>
 </Project>