Added back helper file accidentally deleted during test block 219 migration.

tests/lib_2/mirrors/delegate_class_test.dart

Index: tests/lib_2/mirrors/delegate_class_test.dart
diff --git a/tests/lib_strong/mirrors/delegate_class_test.dart b/tests/lib_2/mirrors/delegate_class_test.dart
similarity index 94%
rename from tests/lib_strong/mirrors/delegate_class_test.dart
rename to tests/lib_2/mirrors/delegate_class_test.dart
index d90e57cd02412f5bf15d95bdb74d49b0270b6c12..83ee8f079d3e2ed092bf236545818056e0e3ba17 100644
--- a/tests/lib_strong/mirrors/delegate_class_test.dart
+++ b/tests/lib_2/mirrors/delegate_class_test.dart
@@ -15,7 +15,6 @@ class C {
   static get getter => 'g';
   static set setter(x) {
     field = x * 2;
-    return 'unobservable value';
   }
 
   static var field;
@@ -28,7 +27,7 @@ class Proxy {
 }
 
 main() {
-  var proxy = new Proxy(reflectClass(C));
+  dynamic proxy = new Proxy(reflectClass(C));
   var result;
 
   Expect.equals('X-Y-Z', proxy.method('X', 'Y', 'Z'));