Instrument analyzer's type analysis and run front_end inference tests.

pkg/front_end/testcases/inference/type_promotion_stopped_by_mutation_in_a_closure.dart

Index: pkg/front_end/testcases/inference/type_promotion_stopped_by_mutation_in_a_closure.dart
diff --git a/pkg/front_end/testcases/inference/type_promotion_stopped_by_mutation_in_a_closure.dart b/pkg/front_end/testcases/inference/type_promotion_stopped_by_mutation_in_a_closure.dart
index da7fc0284ec328e1ed6c016d7b85d25bf44ca974..1d23ed3f6c13f7d19085bde722b26e77598311db 100644
--- a/pkg/front_end/testcases/inference/type_promotion_stopped_by_mutation_in_a_closure.dart
+++ b/pkg/front_end/testcases/inference/type_promotion_stopped_by_mutation_in_a_closure.dart
@@ -2,13 +2,15 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE.md file.
 
+library test;
+
 /*@testedFeatures=inference*/
 main() {
   num n = null;
   if (/*@promotedType=none*/ n is int) {
-    var /*@type=dart.core::num*/ i = /*@promotedType=none*/ n;
+    var /*@type=num*/ i = /*@promotedType=none*/ n;
   }
-  () {
+  /*@type=() → Null*/ () {
     n = null;
   };
 }