Use backend targets to run Kernel transformations in Fasta

pkg/front_end/lib/kernel_generator.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 file.
 
 /// Defines the front-end API for converting source code to Dart Kernel objects.
 library front_end.kernel_generator;
 
 import 'compiler_options.dart';
 import 'dart:async' show Future;
 import 'dart:async';
@@ skipping 35 matching lines @@
   }
 
   var pOptions = new ProcessedOptions(options);
 
   if (!await pOptions.validateOptions()) return null;
 
   try {
     TranslateUri uriTranslator = await pOptions.getUriTranslator();
 
     var dillTarget =
-        new DillTarget(new Ticker(isVerbose: false), uriTranslator, "vm");
+        new DillTarget(new Ticker(isVerbose: false), uriTranslator, "vm_fasta");
     var summary = await pOptions.sdkSummaryProgram;
     if (summary != null) {
       dillTarget.loader.appendLibraries(summary);
     }
 
     var kernelTarget = new KernelTarget(
         options.fileSystem, dillTarget, uriTranslator, options.strongMode);
     kernelTarget.read(source);
 
     await dillTarget.buildOutlines();
@@ skipping 75 matching lines @@
   }
 
   var pOptions = new ProcessedOptions(options);
 
   if (!await pOptions.validateOptions()) return null;
 
   try {
     TranslateUri uriTranslator = await pOptions.getUriTranslator();
 
     var dillTarget =
-        new DillTarget(new Ticker(isVerbose: false), uriTranslator, "vm");
+        new DillTarget(new Ticker(isVerbose: false), uriTranslator, "vm_fasta");
     var summary = await pOptions.sdkSummaryProgram;
     if (summary != null) {
       dillTarget.loader.appendLibraries(summary);
     }
 
     // TODO(sigmund): this is likely not going to work if done naively: if
     // summaries contain external references we need to ensure they are loaded
     // in a specific order.
     for (var inputSummary in await pOptions.inputSummariesPrograms) {
       dillTarget.loader.appendLibraries(inputSummary);
@@ skipping 12 matching lines @@
       kernelTarget.errors.forEach(report);
       return null;
     }
 
     return program;
   } on InputError catch (e) {
     options.onError(new SimpleError(e.format()));
     return null;
   }
 }