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

tests/lib_strong/mirrors/delegate_call_through_getter_test.dart

-// Copyright (c) 2013, 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.invoke_call_through_getter;
-
-import 'dart:mirrors';
-
-import 'package:expect/expect.dart';
-
-class FakeFunctionCall {
-  call(x, y) => '1 $x $y';
-}
-
-class FakeFunctionNSM {
-  noSuchMethod(msg) => msg.positionalArguments.join(', ');
-}
-
-class C {
-  get fakeFunctionCall => new FakeFunctionCall();
-  get fakeFunctionNSM => new FakeFunctionNSM();
-  get closure => (x, y) => '2 $this $x $y';
-  get closureOpt => (x, y, [z, w]) => '3 $this $x $y $z $w';
-  get closureNamed => (x, y, {z, w}) => '4 $this $x $y $z $w';
-  get notAClosure => 'Not a closure';
-  noSuchMethod(msg) => 'DNU';
-
-  toString() => 'C';
-}
-
-class Forwarder {
-  noSuchMethod(msg) => reflect(new C()).delegate(msg);
-}
-
-main() {
-  var f = new Forwarder();
-
-  Expect.equals('1 5 6', f.fakeFunctionCall(5, 6));
-  Expect.equals('7, 8', f.fakeFunctionNSM(7, 8));
-  Expect.equals('2 C 9 10', f.closure(9, 10));
-  Expect.equals('3 C 11 12 13 null', f.closureOpt(11, 12, 13));
-  Expect.equals('4 C 14 15 null 16', f.closureNamed(14, 15, w: 16));
-  Expect.equals('DNU', f.doesNotExist(17, 18));
-  Expect.throws(() => f.closure('wrong arity'), (e) => e is NoSuchMethodError);
-  Expect.throws(() => f.notAClosure(), (e) => e is NoSuchMethodError);
-}