Pass a Target instance to DillTarget instead of its name

pkg/kernel/test/closures/suite.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.md file.
 
 library test.kernel.closures.suite;
 
 import 'dart:async' show Future;
 
 import 'package:front_end/physical_file_system.dart' show PhysicalFileSystem;
 
@@ skipping 23 matching lines @@
 import 'package:front_end/src/fasta/translate_uri.dart' show TranslateUri;
 
 import 'package:front_end/src/fasta/errors.dart' show InputError;
 
 import 'package:front_end/src/fasta/testing/patched_sdk_location.dart';
 
 import 'package:kernel/kernel.dart' show loadProgramFromBinary;
 
 import 'package:kernel/target/targets.dart' show TargetFlags;
 
+import 'package:kernel/target/vm_fasta.dart' show VmFastaTarget;
+
 const String STRONG_MODE = " strong mode ";
 
 class ClosureConversionContext extends ChainContext {
   final bool strongMode;
 
   final TranslateUri uriTranslator;
 
   final List<Step> steps;
 
   ClosureConversionContext(
@@ skipping 40 matching lines @@
 class FastaCompile
     extends Step<TestDescription, Program, ClosureConversionContext> {
   const FastaCompile();
 
   String get name => "fasta compilation";
 
   Future<Result<Program>> run(
       TestDescription description, ClosureConversionContext context) async {
     Program platform = await context.loadPlatform();
     Ticker ticker = new Ticker();
-    DillTarget dillTarget = new DillTarget(
-        ticker, context.uriTranslator, "vm_fasta",
-        flags: new TargetFlags(strongMode: context.strongMode));
+    DillTarget dillTarget = new DillTarget(ticker, context.uriTranslator,
+        new VmFastaTarget(new TargetFlags(strongMode: context.strongMode)));
     platform.unbindCanonicalNames();
     dillTarget.loader.appendLibraries(platform);
     KernelTarget sourceTarget = new KernelTarget(
         PhysicalFileSystem.instance, dillTarget, context.uriTranslator);
 
     Program p;
     try {
       sourceTarget.read(description.uri);
       await dillTarget.buildOutlines();
       await sourceTarget.buildOutlines();
@@ skipping 17 matching lines @@
       CoreTypes coreTypes = new CoreTypes(program);
       program = closure_conversion.transformProgram(coreTypes, program);
       return pass(program);
     } catch (e, s) {
       return crash(e, s);
     }
   }
 }
 
 main(List<String> arguments) => runMe(arguments, createContext, "testing.json");