Fix async/await type checking in analyzer.

tests/language/async_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.
 
 
 import 'package:expect/expect.dart';
 
 import 'dart:async';
 
 topLevelFunction() async { }
 
 Future<int> topLevelWithParameter(int a) async {
   return 7 + a;
 }
 
-int topLevelWithParameterWrongType(int a) async {
+int /// type-mismatch2: static type warning, dynamic type error
+topLevelWithParameterWrongType(int a) async {
   return 7 + a;
 }
 
 var what = 'async getter';
 Future<String> get topLevelGetter async {
   return 'I want to be an ${what}';
 }
 
 class A {
   static int staticVar = 1;
 
   static staticMethod(int param) async => staticVar + param;
   static get staticGetter async => staticVar + 3;
 
   int _x;
   A(this._x);
 
   A.fail() async;  /// constructor2: compile-time error
   factory A.create() async {return null; } /// constructor3: compile-time error
 
-  int someMethod(int param1, int param2, int param3) async => _x + param2;
-  int get getter async { return 5 + _x; }
+  int someMethod(int param1, int param2, int param3) async => _x + param2; /// type-mismatch3: static type warning, dynamic type error
+  int get getter async { return 5 + _x; } /// type-mismatch4: static type warning, dynamic type error
   operator+(A other) async {
     return new A(_x + other._x);
   }
 
   get value => _x;
 }
 
 class B {
   final _y;
   const B._internal(this._y);
   const factory B.createConst(int y) async = A._internal;  /// constructor4: compile-time error
 
   B() : _y = null;
 
   set dontDoThat(value) async {}  /// setter1: compile-time error
 }
 
 
 main() {
   var asyncReturn;
 
   asyncReturn = topLevelFunction();
   Expect.isTrue(asyncReturn is Future);
 
   int a1 = topLevelWithParameter(2);  /// type-mismatch1: static type warning, dynamic type error
-  int a2 = topLevelWithParameterWrongType(2);  /// type-mismatch2: static type warning, dynamic type error
+  int a2 = topLevelWithParameterWrongType(2);  /// type-mismatch2: continued
   asyncReturn = topLevelWithParameter(4);
   Expect.isTrue(asyncReturn is Future);
   asyncReturn.then((int result) => Expect.equals(result, 11));
 
   asyncReturn = topLevelGetter;
   Expect.isTrue(asyncReturn is Future);
   asyncReturn.then((String result) =>
       Expect.stringEquals(result, 'I want to be an async getter'));
 
   asyncReturn = A.staticMethod(2);
   Expect.isTrue(asyncReturn is Future);
   asyncReturn.then((int result) => Expect.equals(result, 3));
 
   asyncReturn = A.staticGetter;
   Expect.isTrue(asyncReturn is Future);
   asyncReturn.then((int result) => Expect.equals(result, 4));
 
   A a = new A(13);
 
-  asyncReturn = a.someMethod(1,2,3);  /// type-mismatch3: static type warning, dynamic type error
+  asyncReturn = a.someMethod(1,2,3);  /// type-mismatch3: continued
   Expect.isTrue(asyncReturn is Future);  /// type-mismatch3: continued
   asyncReturn.then((int result) => Expect.equals(result, 15));  /// type-mismatch3: continued
 
-  asyncReturn = a.getter;  /// type-mismatch4: static type warning, dynamic type error
+  asyncReturn = a.getter;  /// type-mismatch4: continued
   Expect.isTrue(asyncReturn is Future);  /// type-mismatch4: continued
   asyncReturn.then((int result) => Expect.equals(result, 18));  /// type-mismatch4: continued
 
   var b = new A(9);
   asyncReturn = a + b;
   Expect.isTrue(asyncReturn is Future);
   asyncReturn.then((A result) => Expect.equals(result.value, 22));
 
   var foo = 17;
   bar(int p1, p2) async {
@@ skipping 20 matching lines @@
   b2.dontDoThat = 4;  /// setter1: compile-time error
 
   var checkAsync = (var someFunc) {
     var toTest = someFunc();
     Expect.isTrue(toTest is Future);
     toTest.then((int result) => Expect.equals(result, 4));
   };
   checkAsync(() async => 4);
 
 }