Mark outline as external

pkg/front_end/lib/src/fasta/fasta.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.
 
 library fasta;
 
 import 'dart:async' show Future;
 
 import 'dart:convert' show JSON;
 
@@ skipping 129 matching lines @@
     }
     String argument = c.options.arguments.first;
     Uri uri = Uri.base.resolve(argument);
     String path = uriTranslator.translate(uri)?.path ?? argument;
     if (path.endsWith(".dart")) {
       kernelTarget.read(uri);
     } else {
       deprecated_inputError(uri, -1, "Unexpected input: $uri");
     }
     await dillTarget.buildOutlines();
+    dillTarget.loader.libraries.forEach((lib) => lib.isExternal = true);
     var outline = await kernelTarget.buildOutlines();
     if (c.options.dumpIr && output != null) {
       printProgramText(outline, libraryFilter: kernelTarget.isSourceLibrary);
     }
     if (output != null) {
       await writeProgramToFile(outline, output);
       ticker.logMs("Wrote outline to ${output.toFilePath()}");
     }
     return kernelTarget;
   }
@@ skipping 81 matching lines @@
   final BytesBuilder builder = new BytesBuilder();
 
   void add(List<int> data) {
     builder.add(data);
   }
 
   void close() {
     // Nothing to do.
   }
 }