Update expectations for instance creations to match front_end.

pkg/front_end/testcases/inference/generic_methods_iterable_and_future.dart

 // Copyright (c) 2017, 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.
 
 /*@testedFeatures=inference*/
 library test;
 
 import 'dart:async';
 
 Future<int> make(int x) =>
-    (/*@typeArgs=int*/ new Future(/*@returnType=int*/ () => x));
+    (new /*@typeArgs=int*/ Future(/*@returnType=int*/ () => x));
 
 main() {
   Iterable<Future<int>> list = <int>[1, 2, 3].map(make);
   Future<List<int>> results = Future.wait(/*@promotedType=none*/ list);
   Future<String> results2 = /*@promotedType=none*/ results.then(
       /*@returnType=FutureOr<String>*/ (List<int> list) => list.fold(
           '',
           /*@returnType=FutureOr<String>*/ (/*@type=FutureOr<String>*/ x,
                   /*@type=int*/ y) => /*info:DYNAMIC_CAST,info:DYNAMIC_INVOKE*/ x /*error:UNDEFINED_OPERATOR*/ +
               y.toString()));
 
   Future<String> results3 = /*@promotedType=none*/ results.then(
       /*@returnType=FutureOr<String>*/ (List<int> list) => list.fold(
           '',
           /*info:INFERRED_TYPE_CLOSURE,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ /*@returnType=String*/ (String
                       x,
                   /*@type=int*/ y) =>
               x + y.toString()));
 
   Future<String> results4 = /*@promotedType=none*/ results.then(
       /*@returnType=String*/ (List<int> list) => list.fold<String>(
           '',
           /*@returnType=String*/ (/*@type=String*/ x, /*@type=int*/ y) =>
               x + y.toString()));
 }