Merge pull request #23412 from sharwell/InternalsVisibleToCompletionProvider_NRE_Fix

Fix for #22690 NRE in GetAttributeSyntaxNodeOfToken

src/Features/Core/Portable/Completion/Providers/AbstractInternalsVisibleToCompletionProvider.cs

@@ -75,7 +75,7 @@ private static SyntaxNode GetAttributeSyntaxNodeOfToken(ISyntaxFactsService synt
             //[Attribute(""|
             //[Attribute("Text"|)
             var node = token.Parent;
-            if (syntaxFactsService.IsStringLiteralExpression(node))
+            if (node != null && syntaxFactsService.IsStringLiteralExpression(node))
             {
                 // Edge case: ElementAccessExpressionSyntax is present if the following statement is another attribute:
                 //   [assembly: System.Runtime.CompilerServices.InternalsVisibleTo("|
@@ -250,4 +250,4 @@ private static string GetPublicKeyAsHexString(ImmutableArray<byte> publicKey)
             return pooledStrBuilder.ToStringAndFree();
         }
     }
-}
\ No newline at end of file
+}