Support constructor declarations in analyzer2dart.

pkg/analyzer2dart/test/end2end_data.dart

 // Copyright (c) 2014, 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.
 
 /// Test data for the end2end test.
 library test.end2end.data;
 
 import 'test_helper.dart';
 
 class TestSpec extends TestSpecBase {
@@ skipping 799 matching lines @@
 ''', '''
 main(a) {
   return (a ? () {
     return 0;
   } : () {
     return 1;
   })();
 }
 '''),
   ]),
+
+  const Group('Constructors', const <TestSpec>[
+    const TestSpec('''
+class C {
+  C() {}
+}
+main() {
+  return new C();
+}
+'''),
+  ]),
 ];