Added InterfaceMirror.newInstance().

tests/lib/mirrors/mirrors_test.dart

 // Copyright (c) 2011, 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.
 
 // TODO(rmacnak): Move the existing mirror tests here (a place for 
 // cross-implementation tests).
 
 #library("MirrorsTest.dart");
 #import("dart:mirrors");
 #import("../../../lib/unittest/unittest.dart");
 
 var topLevelField;
 
 class Class {
+  Class() { this.field = "default value"; }
+  Class.withInitialValue(this.field);
   var field;
   static var staticField;
 }
 
 testFieldAccess(mirrors) {
   var instance = new Class();
 
   var libMirror = mirrors.libraries()["MirrorsTest.dart"];
   var classMirror = libMirror.classes()["Class"];
   var instMirror = mirrors.mirrorOf(instance);
@@ skipping 29 matching lines @@
   var funcMirror = mirror.function();
   expect(funcMirror is MethodMirror, equals(true));
   expect(funcMirror.parameters().length, equals(3));
 
   var future = mirror.apply([2, 4, 8]);
   future.then(expectAsync1((resultMirror) {
     expect(resultMirror.reflectee, equals(14));
   }));
 }
 
+testInvokeConstructor(mirrors) {
+  var libMirror = mirrors.libraries()["MirrorsTest.dart"];
+  var classMirror = libMirror.classes()["Class"];
+  
+  var future = classMirror.newInstance('', []);
+  future.then(expectAsync1((resultMirror) {
+    var instance = resultMirror.reflectee;
+    expect(instance is Class, equals(true));
+    expect(instance.field, equals("default value"));
+  }));
+
+  future = classMirror.newInstance('withInitialValue', [45]);
+  future.then(expectAsync1((resultMirror) {
+    var instance = resultMirror.reflectee;
+    expect(instance is Class, equals(true));
+    expect(instance.field, equals(45));
+  }));
+}
+
 main() {
   var mirrors = currentMirrorSystem();
 
   test("Test field access", () { testFieldAccess(mirrors); });
   test("Test closure mirrors", () { testClosureMirrors(mirrors); });
+  test("Test invoke constructor", () { testInvokeConstructor(mirrors); });
 }