Pass a Target instance to DillTarget instead of its name

pkg/front_end/test/fasta/testing/suite.dart

 // Copyright (c) 2016, 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 fasta.testing.suite;
 
 import 'dart:async' show Future;
 
 import 'dart:io' show File;
 
@@ skipping 34 matching lines @@
 
 import 'package:front_end/src/fasta/kernel/kernel_target.dart'
     show KernelTarget;
 
 import 'package:front_end/src/fasta/dill/dill_target.dart' show DillTarget;
 
 import 'package:kernel/kernel.dart' show loadProgramFromBytes;
 
 import 'package:kernel/target/targets.dart' show TargetFlags;
 
+import 'package:kernel/target/vm_fasta.dart' show VmFastaTarget;
+
 export 'package:testing/testing.dart' show Chain, runMe;
 
 const String STRONG_MODE = " strong mode ";
 
 const String ENABLE_FULL_COMPILE = " full compile ";
 
 const String AST_KIND_INDEX = " AST kind index ";
 
 const String EXPECTATIONS = '''
 [
@@ skipping 146 matching lines @@
 
   bool get isCompiler => fullCompile;
 
   Future<Result<Program>> run(
       TestDescription description, FastaContext context) async {
     // Disable colors to ensure that expectation files are the same across
     // platforms and independent of stdin/stderr.
     CompilerContext.current.disableColors();
     Program platformOutline = await context.loadPlatformOutline();
     Ticker ticker = new Ticker();
-    DillTarget dillTarget = new DillTarget(
-        ticker, context.uriTranslator, "vm_fasta",
-        flags: new TargetFlags(strongMode: strongMode));
+    DillTarget dillTarget = new DillTarget(ticker, context.uriTranslator,
+        new VmFastaTarget(new TargetFlags(strongMode: strongMode)));
     platformOutline.unbindCanonicalNames();
     dillTarget.loader.appendLibraries(platformOutline);
     // We create a new URI translator to avoid reading plaform libraries from
     // file system.
     TranslateUri uriTranslator = new TranslateUri(
         context.uriTranslator.packages,
         const <String, Uri>{},
         const <String, List<Uri>>{});
     KernelTarget sourceTarget = astKind == AstKind.Analyzer
         ? new AnalyzerTarget(dillTarget, uriTranslator, strongMode)
@@ skipping 21 matching lines @@
             return fail(null, instrumentation.problemsAsString);
           }
         }
       }
     } on InputError catch (e, s) {
       return fail(null, e.error, s);
     }
     return pass(p);
   }
 }