Use mirror-free LRU test for dart2js

tests/lib/mirrors/lru_expect.dart

Index: tests/lib/mirrors/lru_expect.dart
diff --git a/tests/lib/mirrors/lru_test.dart b/tests/lib/mirrors/lru_expect.dart
similarity index 68%
copy from tests/lib/mirrors/lru_test.dart
copy to tests/lib/mirrors/lru_expect.dart
index 141fc989d0694a29ed09878b082f5033c3a9e623..a048fcbbafa3ecbd95ff25d4996257f61ab01bb3 100644
--- a/tests/lib/mirrors/lru_test.dart
+++ b/tests/lib/mirrors/lru_expect.dart
@@ -2,20 +2,13 @@
 // 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 "dart:mirrors";
 import "package:expect/expect.dart";
 
-newLRUMapWithShift(int shift) {
-  var lib = currentMirrorSystem().libraries[Uri.parse("dart:_internal")];
-  var cls = lib.declarations[#LRUMap];
-  return cls.newInstance(#withShift, [shift]).reflectee;
-}
-
-main() {
-  Expect.throws(() => newLRUMapWithShift(0), (e) => e is Exception);
+expect(lruMapFactory) {
+  Expect.throws(() => lruMapFactory(0), (e) => e is Exception);
 
   for (int shift = 1; shift < 5; shift++) {
-    var map = newLRUMapWithShift(shift);
+    var map = lruMapFactory(shift);
     var capacity = (1 << shift) * 3 ~/ 4;
     for (int value = 0; value < 100; value++) {
       var key = "$value";
@@ -31,4 +24,4 @@ main() {
       Expect.equals(value, map[key]);
     }
   }
-}
+}