Add mirrors tests

test/codegen/lib/mirrors/delegate_library_test.dart

+// Copyright (c) 2015, 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.
+
+library test.delegate_library;
+
+import 'dart:mirrors';
+
+import 'package:expect/expect.dart';
+
+method(a, b, c) => "$a-$b-$c";
+methodWithNamed(a, {b:'B', c}) => "$a-$b-$c";
+methodWithOpt(a, [b, c='C']) => "$a-$b-$c";
+get getter => 'g';
+set setter(x) {
+  field = x*2;
+  return 'unobservable value';
+}
+var field;
+
+
+class Proxy {
+  var targetMirror;
+  Proxy(this.targetMirror);
+  noSuchMethod(invocation) => targetMirror.delegate(invocation);
+}
+
+main() {
+  var proxy = new Proxy(reflectClass(Proxy).owner);
+  var result;
+
+  Expect.equals('X-Y-Z', proxy.method('X', 'Y', 'Z'));
+
+  Expect.equals('X-B-null', proxy.methodWithNamed('X'));
+  Expect.equals('X-Y-null', proxy.methodWithNamed('X', b: 'Y'));
+  Expect.equals('X-Y-Z', proxy.methodWithNamed('X', b: 'Y', c: 'Z'));
+
+  Expect.equals('X-null-C', proxy.methodWithOpt('X'));
+  Expect.equals('X-Y-C', proxy.methodWithOpt('X', 'Y'));
+  Expect.equals('X-Y-Z', proxy.methodWithOpt('X', 'Y', 'Z'));
+
+  Expect.equals('g', proxy.getter);
+
+  Expect.equals(5, proxy.setter = 5);
+  Expect.equals(10, proxy.field);
+
+  Expect.equals(5, proxy.field = 5);
+  Expect.equals(5, proxy.field);
+}