Fix annotation of generic method invocations in Fasta inference tests.

pkg/front_end/testcases/inference/future_then_4.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';
 
 class MyFuture<T> implements Future<T> {
   MyFuture() {}
   MyFuture.value(T x) {}
   dynamic noSuchMethod(invocation);
   MyFuture<S> then<S>(FutureOr<S> f(T x), {Function onError}) => null;
 }
 
 void main() {
   MyFuture f;
-  MyFuture<int> t1 = /*@promotedType=none*/ f.then(
+  MyFuture<int> t1 = /*@promotedType=none*/ f. /*@typeArgs=int*/ then(
       /*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async =>
           await new MyFuture<int>.value(3));
-  MyFuture<int> t2 = /*@promotedType=none*/ f
-      .then(/*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async {
+  MyFuture<int> t2 = /*@promotedType=none*/ f. /*@typeArgs=int*/ then(
+      /*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async {
     return await new MyFuture<int>.value(3);
   });
-  MyFuture<int> t3 = /*@promotedType=none*/ f
-      .then(/*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async => 3);
-  MyFuture<int> t4 = /*@promotedType=none*/ f
-      .then(/*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async {
+  MyFuture<int> t3 = /*@promotedType=none*/ f. /*@typeArgs=int*/ then(
+      /*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async => 3);
+  MyFuture<int> t4 = /*@promotedType=none*/ f. /*@typeArgs=int*/ then(
+      /*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async {
     return 3;
   });
-  MyFuture<int> t5 = /*@promotedType=none*/ f.then(
+  MyFuture<int> t5 = /*@promotedType=none*/ f. /*@typeArgs=int*/ then(
       /*@returnType=MyFuture<int>*/ (/*@type=dynamic*/ _) =>
           new MyFuture<int>.value(3));
-  MyFuture<int> t6 = /*@promotedType=none*/ f
-      .then(/*@returnType=MyFuture<int>*/ (/*@type=dynamic*/ _) {
+  MyFuture<int> t6 = /*@promotedType=none*/ f. /*@typeArgs=int*/ then(
+      /*@returnType=MyFuture<int>*/ (/*@type=dynamic*/ _) {
     return new MyFuture<int>.value(3);
   });
-  MyFuture<int> t7 = /*@promotedType=none*/ f.then(
+  MyFuture<int> t7 = /*@promotedType=none*/ f. /*@typeArgs=int*/ then(
       /*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async =>
           new MyFuture<int>.value(3));
-  MyFuture<int> t8 = /*@promotedType=none*/ f
-      .then(/*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async {
+  MyFuture<int> t8 = /*@promotedType=none*/ f. /*@typeArgs=int*/ then(
+      /*@returnType=Future<int>*/ (/*@type=dynamic*/ _) async {
     return new MyFuture<int>.value(3);
   });
 }