Merge pull request #1385 from microsoft/fix1369

Fix NRE thrown from friendly overloads with optional pointer parameters

Author: AArnott

src/Microsoft.Windows.CsWin32/Generator.FriendlyOverloads.cs

@@ -607,8 +607,8 @@ private IEnumerable<MethodDeclarationSyntax> DeclareFriendlyOverloads(MethodDefi
                         ArgumentList().AddArguments(Argument(LiteralExpression(SyntaxKind.NullLiteralExpression))));
                 arguments[param.SequenceNumber - 1] = Argument(ConditionalExpression(
                     MemberAccessExpression(SyntaxKind.SimpleMemberAccessExpression, origName, IdentifierName("HasValue")),
-                    localName,
-                    nullRef));
+                    RefExpression(localName),
+                    RefExpression(nullRef)));
             }
 
             bool TryHandleCountParam(TypeSyntax elementType, bool nullableSource)