Record names of classes which unnamed constructor are used in SuperConstructorInvocation.

pkg/analyzer/test/src/task/dart_test.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.test.src.task.dart_test;
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart';
@@ skipping 3677 matching lines @@
   }
 }
 ''');
     expect(info.names, unorderedEquals(['A', 'B', 'C']));
     expect(info.superToSubs.keys, isEmpty);
     expect(info.instantiatedNames, isEmpty);
     expect(info.userToDependsOn.keys, unorderedEquals(['U']));
     expect(info.userToDependsOn['U'], unorderedEquals(['A', 'B']));
   }
 
+  test_class_extendedUsedUnnamedConstructorNames() {
+    ReferencedNames info = _computeReferencedNames('''
+class U1 extends A {
+  U1() : super();
+}
+class U2 extends p.B {
+  U2() : super();
+}
+class U3 extends p.C {
+  U3() : super.named();
+}
+''');
+    expect(
+        info.extendedUsedUnnamedConstructorNames, unorderedEquals(['A', 'B']));
+  }
+
   test_class_field() {
     ReferencedNames info = _computeReferencedNames('''
 class U {
   A f = new B();
 }
 ''');
     expect(info.names, unorderedEquals(['A', 'B']));
     expect(info.superToSubs.keys, isEmpty);
     expect(info.instantiatedNames, unorderedEquals(['B']));
     expect(info.userToDependsOn.keys, unorderedEquals(['U']));
@@ skipping 2075 matching lines @@
   /**
    * Fill [errorListener] with [result] errors in the current [task].
    */
   void _fillErrorListener(ResultDescriptor<List<AnalysisError>> result) {
     List<AnalysisError> errors = task.outputs[result] as List<AnalysisError>;
     expect(errors, isNotNull, reason: result.name);
     errorListener = new GatheringErrorListener();
     errorListener.addAll(errors);
   }
 }