Work around bug where closures are missing #call to support delegation of #call to closures.

tests/lib/mirrors/delegate_function_invocation_test.dart

+// Copyright (c) 2014, 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.delgate_function_invocation;
+
+import 'dart:mirrors';
+
+import 'package:expect/expect.dart';
+
+class Proxy {
+  var targetMirror;
+  Proxy(target) : this.targetMirror = reflect(target);
+  noSuchMethod(invocation) => targetMirror.delegate(invocation);
+}
+
+testClosure() {
+  var proxy = new Proxy(() => 42);
+  Expect.equals(reflect(42), proxy());
+  Expect.equals(reflect(42), proxy.call());
+}
+
+class FakeFunction {
+  call() => 43;
+}
+
+testFakeFunction() {
+  var proxy = new Proxy(new FakeFunction());
+  Expect.equals(reflect(43), proxy());
+  Expect.equals(reflect(43), proxy.call());
+}
+
+topLevelFunction() => 44;
+
+testTopLevelTearOff() {
+  var proxy = new Proxy(topLevelFunction);
+  Expect.equals(reflect(44), proxy());
+  Expect.equals(reflect(44), proxy.call());
+}
+
+class C {
+  method() => 45;
+}
+
+testInstanceTearOff() {
+  var proxy = new Proxy(new C().method);
+  Expect.equals(reflect(45), proxy());
+  Expect.equals(reflect(45), proxy.call());
+}
+
+main() {
+  testClosure();
+  testFakeFunction();
+  testTopLevelTearOff();
+  testInstanceTearOff();
+}