Support new function subtyping rules in dart2js.

tests/compiler/dart2js/subtype_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 subtype_test;
 
 import 'package:expect/expect.dart';
 import 'type_test_helper.dart';
 import '../../../sdk/lib/_internal/compiler/implementation/dart_types.dart';
 import "../../../sdk/lib/_internal/compiler/implementation/elements/elements.dart"
@@ skipping 344 matching lines @@
 
 testFunctionSubtypingOptional() {
   var env = new TypeEnvironment(r"""
       void void_() {}
       void void__int(int i) {}
       void void___int([int i]) {}
       void void___int2([int i]) {}
       void void___Object([Object o]) {}
       void void__int__int(int i1, [int i2]) {}
       void void__int__int2(int i1, [int i2]) {}
+      void void__int__int_int(int i1, [int i2, int i3]);
       void void___double(double d) {}
       void void___int_int([int i1, int i2]) {}
+      void void___int_int_int([int i1, int i2, int i3]);

[karlklose, 2013/04/24 11:59:20]

This is not used, is it?

[Johnni Winther, 2013/04/25 07:54:12]

Done.

       void void___Object_int([Object o, int i]) {}
       """);
   functionSubtypingOptionalHelper(env);
 }
 
 testTypedefSubtypingOptional() {
   var env = new TypeEnvironment(r"""
       typedef void void_();
       typedef void void__int(int i);
       typedef void void___int([int i]);
       typedef void void___int2([int i]);
       typedef void void___Object([Object o]);
       typedef void void__int__int(int i1, [int i2]);
       typedef void void__int__int2(int i1, [int i2]);
+      typedef void void__int__int_int(int i1, [int i2, int i3]);
       typedef void void___double(double d);
       typedef void void___int_int([int i1, int i2]);
+      typedef void void___int_int_int([int i1, int i2, int i3]);

[karlklose, 2013/04/24 11:59:20]

Ditto.

[Johnni Winther, 2013/04/25 07:54:12]

Done.

       typedef void void___Object_int([Object o, int i]);
       """);
   functionSubtypingOptionalHelper(env);
 }
 
 functionSubtypingOptionalHelper(TypeEnvironment env) {
   expect(bool expectedResult, String sub, String sup) {
     DartType subtype = env.getElementType(sub);
     DartType supertype = env.getElementType(sup);
     Expect.equals(expectedResult, env.isSubtype(subtype, supertype),
         '$subtype <: $supertype');
   }
 
   // Test ([int])->void <: ()->void.
   expect(true, 'void___int', 'void_');
   // Test ([int])->void <: (int)->void.
-  expect(false, 'void___int', 'void__int');
+  expect(true, 'void___int', 'void__int');
   // Test (int)->void <: ([int])->void.
   expect(false, 'void__int', 'void___int');
   // Test ([int])->void <: ([int])->void.
   expect(true, 'void___int', 'void___int2');
   // Test ([Object])->void <: ([int])->void.
   expect(true, 'void___Object', 'void___int');
   // Test ([int])->void <: ([Object])->void.
   expect(true, 'void___int', 'void___Object');
   // Test (int,[int])->void <: (int,[int])->void.
   expect(true, 'void__int__int', 'void__int__int2');
+  // Test (int)->void <: ([int])->void.
+  expect(false, 'void__int', 'void___int');
+  // Test ([int,int])->void <: (int)->void.
+  expect(true, 'void___int_int', 'void__int');
+  // Test ([int,int])->void <: (int,[int])->void.
+  expect(true, 'void___int_int', 'void__int__int');
+  // Test ([int,int])->void <: (int,[int,int])->void.
+  expect(false, 'void___int_int', 'void__int__int_int');
   // Test ([int])->void <: ([double])->void.
   expect(false, 'void___int', 'void___double');
   // Test ([int])->void <: ([int,int])->void.
   expect(false, 'void___int', 'void___int_int');
   // Test ([int,int])->void <: ([int])->void.
   expect(true, 'void___int_int', 'void___int');
   // Test ([Object,int])->void <: ([int])->void.
   expect(true, 'void___Object_int', 'void___int');
 }
 
@@ skipping 284 matching lines @@
   expect(true, J_U, Object_);
   expect(false, J_U, num_);
   expect(false, J_U, int_);
   expect(false, J_U, String_);
   expect(true, J_U, dynamic_);
   expect(false, J_U, J_T);
   expect(true, J_U, J_S);
   expect(true, J_U, J_U);
   expect(false, J_U, A_T);
 }