Clone and link all tokens in AstCloner.

pkg/analyzer/lib/src/dart/ast/ast.dart

Index: pkg/analyzer/lib/src/dart/ast/ast.dart
diff --git a/pkg/analyzer/lib/src/dart/ast/ast.dart b/pkg/analyzer/lib/src/dart/ast/ast.dart
index 26e3b760ecacbd5983f0c9fa3776b2da3a86e86e..342d4a69f7df7fc0294b306fbe821bd14c6ce77b 100644
--- a/pkg/analyzer/lib/src/dart/ast/ast.dart
+++ b/pkg/analyzer/lib/src/dart/ast/ast.dart
@@ -1957,6 +1957,14 @@ class ClassTypeAliasImpl extends TypeAliasImpl implements ClassTypeAlias {
       _name != null ? (_name.staticElement as ClassElement) : null;
 
   @override
+  Token get firstTokenAfterCommentAndMetadata {
+    if (abstractKeyword != null) {
+      return abstractKeyword;
+    }
+    return typedefKeyword;
+  }
+
+  @override
   ImplementsClause get implementsClause => _implementsClause;
 
   @override