Add check for constness in constructor redirection

tests/language/regress_27617_test.dart

Index: tests/language/regress_27617_test.dart
diff --git a/pkg/dev_compiler/test/codegen/language/static_field_override3_test.dart b/tests/language/regress_27617_test.dart
similarity index 50%
copy from pkg/dev_compiler/test/codegen/language/static_field_override3_test.dart
copy to tests/language/regress_27617_test.dart
index a33147d67816c83f659a9c07334e0f72beeaad89..9a0fdbd9f9f21787e347ba48b45b2c431269884b 100644
--- a/pkg/dev_compiler/test/codegen/language/static_field_override3_test.dart
+++ b/tests/language/regress_27617_test.dart
@@ -2,16 +2,15 @@
 // 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.
 
-import 'package:expect/expect.dart';
 
 class Foo {
-  static int x = 42;
-}
+  final String greeting;
+  Foo._(this.greeting) { }
 
-class Bar extends Foo {
-  static int x = 12;
+  // Const constructor must not redirect to non-const constructor.
+  const Foo.hi() : this._('hi');  /// 1: compile-time error
 }
 
-void main() {
-  Expect.equals(12, Bar.x);
-}
+main() {
+  const h = const Foo.hi();  /// 1: continued
+}