Simplify type names shoudl nto simplify to 'var'

src/Features/CSharp/Portable/SimplifyTypeNames/SimplifyTypeNamesCodeFixProvider.cs

@@ -43,7 +43,8 @@ protected override string GetTitle(string diagnosticId, string nodeText)
 
         protected override SyntaxNode AddSimplificationAnnotationTo(SyntaxNode expressionSyntax)
         {
-            var annotatedexpressionSyntax = expressionSyntax.WithAdditionalAnnotations(Simplifier.Annotation, Formatter.Annotation);
+            var annotatedexpressionSyntax = expressionSyntax.WithAdditionalAnnotations(
+                Simplifier.Annotation, Formatter.Annotation, DoNotAllowVarAnnotation.Annotation);
 
             if (annotatedexpressionSyntax.Kind() == SyntaxKind.IsExpression || annotatedexpressionSyntax.Kind() == SyntaxKind.AsExpression)
             {

src/Features/Core/Portable/SimplifyTypeNames/AbstractSimplifyTypeNamesCodeFixProvider.cs

@@ -109,14 +109,6 @@ public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
             }
         }
 
-        private async Task<Document> SimplifyTypeNameAsync(Document document, SyntaxNode node, CancellationToken cancellationToken)
-        {
-            var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
-
-            return document.WithSyntaxRoot(
-                root.ReplaceNode(node, AddSimplificationAnnotationTo(node)));
-        }
-
         private bool CanSimplifyTypeNameExpression(SemanticModel model, SyntaxNode node, OptionSet optionSet, TextSpan span, out string diagnosticId, CancellationToken cancellationToken)
         {
             diagnosticId = null;