Annotate targets of implicit this property gets/sets in inference tests.

pkg/front_end/testcases/inference/constructors_inference_f_bounded.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;
 
 class Clonable<T> {}
 
 class Pair<T extends Clonable<T>, U extends Clonable<U>> {
   T t;
   U u;
   Pair(this.t, this.u);
   Pair._();
-  Pair<U, T> get reversed => new /*@typeArgs=Pair::U, Pair::T*/ Pair(u, t);
+  Pair<U, T> get reversed => new /*@typeArgs=Pair::U, Pair::T*/ Pair(
+      /*@target=Pair::u*/ u,
+      /*@target=Pair::t*/ t);
 }
 
 main() {
   final /*@type=Pair<Clonable<dynamic>, Clonable<dynamic>>*/ x =
       new /*error:COULD_NOT_INFER,error:COULD_NOT_INFER*/ /*@typeArgs=Clonable<dynamic>, Clonable<dynamic>*/ Pair
           ._();
 }