DynamicMethod permit ref returns in .NET Core 2.1+ (#9335)

Fixes dotnet/runtime#92670

Author: jkotas

xml/System.Reflection.Emit/DynamicMethod.xml

@@ -219,7 +219,7 @@
         <exception cref="T:System.ArgumentException">An element of <paramref name="parameterTypes" /> is <see langword="null" /> or <see cref="T:System.Void" />.</exception>
         <exception cref="T:System.ArgumentNullException">
           <paramref name="name" /> is <see langword="null" />.</exception>
-        <exception cref="T:System.NotSupportedException">
+        <exception cref="T:System.NotSupportedException">.NET Framework and .NET Core versions older than 2.1:
           <paramref name="returnType" /> is a type for which <see cref="P:System.Type.IsByRef" /> returns <see langword="true" />.</exception>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/how-to-define-and-execute-dynamic-methods">How to: Define and Execute Dynamic Methods</related>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/security-issues-in-reflection-emit">Security Issues in Reflection Emit</related>
@@ -326,7 +326,7 @@
         <exception cref="T:System.ArgumentException">An element of <paramref name="parameterTypes" /> is <see langword="null" /> or <see cref="T:System.Void" />.</exception>
         <exception cref="T:System.ArgumentNullException">
           <paramref name="name" /> is <see langword="null" />.</exception>
-        <exception cref="T:System.NotSupportedException">
+        <exception cref="T:System.NotSupportedException">.NET Framework and .NET Core versions older than 2.1:
           <paramref name="returnType" /> is a type for which <see cref="P:System.Type.IsByRef" /> returns <see langword="true" />.</exception>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/how-to-define-and-execute-dynamic-methods">How to: Define and Execute Dynamic Methods</related>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/security-issues-in-reflection-emit">Security Issues in Reflection Emit</related>
@@ -430,7 +430,7 @@
  -or-  
 
  <paramref name="m" /> is <see langword="null" />.</exception>
-        <exception cref="T:System.NotSupportedException">
+        <exception cref="T:System.NotSupportedException">.NET Framework and .NET Core versions older than 2.1:
           <paramref name="returnType" /> is a type for which <see cref="P:System.Type.IsByRef" /> returns <see langword="true" />.</exception>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/how-to-define-and-execute-dynamic-methods">How to: Define and Execute Dynamic Methods</related>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/security-issues-in-reflection-emit">Security Issues in Reflection Emit</related>
@@ -546,8 +546,8 @@
  -or-  
 
  <paramref name="owner" /> is <see langword="null" />.</exception>
-        <exception cref="T:System.NotSupportedException">
-          <paramref name="returnType" /> is <see langword="null" />, or is a type for which <see cref="P:System.Type.IsByRef" /> returns <see langword="true" />.</exception>
+        <exception cref="T:System.NotSupportedException">.NET Framework and .NET Core versions older than 2.1:
+          <paramref name="returnType" /> is a type for which <see cref="P:System.Type.IsByRef" /> returns <see langword="true" />.</exception>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/how-to-define-and-execute-dynamic-methods">How to: Define and Execute Dynamic Methods</related>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/security-issues-in-reflection-emit">Security Issues in Reflection Emit</related>
       </Docs>
@@ -645,7 +645,7 @@
  -or-  
 
  <paramref name="m" /> is <see langword="null" />.</exception>
-        <exception cref="T:System.NotSupportedException">
+        <exception cref="T:System.NotSupportedException">.NET Framework and .NET Core versions older than 2.1:
           <paramref name="returnType" /> is a type for which <see cref="P:System.Type.IsByRef" /> returns <see langword="true" />.</exception>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/how-to-define-and-execute-dynamic-methods">How to: Define and Execute Dynamic Methods</related>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/security-issues-in-reflection-emit">Security Issues in Reflection Emit</related>
@@ -744,8 +744,8 @@
  -or-  
 
  <paramref name="owner" /> is <see langword="null" />.</exception>
-        <exception cref="T:System.NotSupportedException">
-          <paramref name="returnType" /> is <see langword="null" />, or is a type for which <see cref="P:System.Type.IsByRef" /> returns <see langword="true" />.</exception>
+        <exception cref="T:System.NotSupportedException">.NET Framework and .NET Core versions older than 2.1:
+          <paramref name="returnType" /> is a type for which <see cref="P:System.Type.IsByRef" /> returns <see langword="true" />.</exception>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/how-to-define-and-execute-dynamic-methods">How to: Define and Execute Dynamic Methods</related>
         <related type="Article" href="/dotnet/framework/reflection-and-codedom/security-issues-in-reflection-emit">Security Issues in Reflection Emit</related>
       </Docs>