Include types of ClassTypeAlias into subtyped names.

pkg/analyzer/lib/src/dart/analysis/referenced_names.dart

Index: pkg/analyzer/lib/src/dart/analysis/referenced_names.dart
diff --git a/pkg/analyzer/lib/src/dart/analysis/referenced_names.dart b/pkg/analyzer/lib/src/dart/analysis/referenced_names.dart
index 4733e2fe98687f2fb88cb0c0462db70047980850..d1fe93bf7deedfb39955d1ee06c428ed4e40bce4 100644
--- a/pkg/analyzer/lib/src/dart/analysis/referenced_names.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/referenced_names.dart
@@ -41,6 +41,10 @@ Set<String> computeSubtypedNames(CompilationUnit unit) {
       _addSubtypedName(declaration.extendsClause?.superclass);
       _addSubtypedNames(declaration.withClause?.mixinTypes);
       _addSubtypedNames(declaration.implementsClause?.interfaces);
+    } else if (declaration is ClassTypeAlias) {
+      _addSubtypedName(declaration.superclass);
+      _addSubtypedNames(declaration.withClause?.mixinTypes);
+      _addSubtypedNames(declaration.implementsClause?.interfaces);
     }
   }