dart2js rti fix: functions are subtypes of Object

tests/language/function_subtype1_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.
 // Dart test program for constructors and initializers.
 
 // Check function subtyping.
 
 import 'package:expect/expect.dart';
 
 class C<T> {}
 
 typedef _();
 typedef void void_();
 typedef void void_2();
 typedef int int_();
 typedef int int_2();
 typedef Object Object_();
 typedef double double_();
 typedef void void__int(int i);
+typedef void void__Object(Object o);
 typedef int int__int(int i);
 typedef int int__int2(int i);
 typedef int int__Object(Object o);
 typedef Object Object__int(int i);
 typedef int int__double(double d);
 typedef int int__int_int(int i1, int i2);
 typedef void inline_void_(void f());
 typedef void inline_void__int(void f(int i));
 
 main() {
@@ skipping 32 matching lines @@
   // (int) -> int <: (double) -> int
   Expect.isFalse(new C<int__int>() is C<int__double>);
   // () -> int <: (int) -> int
   Expect.isFalse(new C<int_>() is C<int__int>);
   // (int) -> int <: (int,int) -> int
   Expect.isFalse(new C<int__int>() is C<int__int_int>);
   // (int,int) -> int <: (int) -> int
   Expect.isFalse(new C<int__int_int>() is C<int__int>);
   // (()->void) -> void <: ((int)->void) -> void
   Expect.isFalse(new C<inline_void_>() is C<inline_void__int>);
+  // (Object) -> void <: ((int)->void) -> void
+  Expect.isTrue(new C<void__Object>() is C<inline_void__int>);
   // ((int)->void) -> void <: (()->void) -> void
   Expect.isFalse(new C<inline_void__int>() is C<inline_void_>);
 }