Ensure that constant field initializers are canonicalized

tests/language/regress_27164_test.dart

 // Copyright (c) 2016, 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.
 
+// Regression test for issue 27164.
+
 import 'package:expect/expect.dart';
 
-class Foo {
-  static int get x => 42;
-  static void set x(value) {}
-}
+String simpleEcho(String arg) => arg;
 
-class Bar extends Foo {
-  static int x = 12;
+class Echo {
+  final echo;
+  // Check that the expression simpleEcho is a compile-time constant.
+  const Echo() : echo = simpleEcho;
 }
 
 void main() {
-  Expect.equals(12, Bar.x);
-}
+  Expect.equals("hello", const Echo().echo("hello"));
+}
+