Fix annotation of promoted parameters in Fasta inference tests.

pkg/front_end/testcases/inference/block_bodied_lambdas_lub.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:math' show Random;
 
 test2() {
   List<num> o;
   var /*@type=Iterable<num>*/ y = /*@promotedType=none*/ o
       .map(/*@returnType=num*/ (/*@type=num*/ x) {
     if (new Random().nextBool()) {
-      return x.toInt() + 1;
+      return /*@promotedType=none*/ x.toInt() + 1;
     } else {
-      return x.toDouble();
+      return /*@promotedType=none*/ x.toDouble();
     }
   });
   Iterable<num> w = /*@promotedType=none*/ y;
   Iterable<int> z = /*info:ASSIGNMENT_CAST*/ /*@promotedType=none*/ y;
 }