Support references to unserialized libraries.

tests/compiler/dart2js/serialization/helper.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 dart2js.serialization_helper;
 
 import 'dart:async';
 import 'dart:io';
 
 import 'package:compiler/src/commandline_options.dart';
@@ skipping 70 matching lines @@
 
     for (int index = first; index <= last; index++) {
       Test test = TESTS[index];
       List<SerializedData> dataList =
           await preserializeData(serializedData, test);
       Map<String, String> sourceFiles = <String, String>{};
       sourceFiles.addAll(test.sourceFiles);
       if (test.preserializedSourceFiles != null) {
         sourceFiles.addAll(test.preserializedSourceFiles);
       }
+      if (test.unserializedSourceFiles != null) {
+        sourceFiles.addAll(test.unserializedSourceFiles);
+      }
       List<Uri> resolutionInputs = <Uri>[];
       for (SerializedData data in dataList) {
         data.expandMemorySourceFiles(sourceFiles);
         data.expandUris(resolutionInputs);
       }
       await testFunction(entryPoint,
           sourceFiles: sourceFiles,
           resolutionInputs: resolutionInputs,
           index: index,
           test: test,
@@ skipping 88 matching lines @@
     SerializedData serializedData, Test test) async {
   if (test == null ||
       test.preserializedSourceFiles == null ||
       test.preserializedSourceFiles.isEmpty) {
     return <SerializedData>[serializedData];
   }
   List<Uri> uriList = <Uri>[];
   for (String key in test.preserializedSourceFiles.keys) {
     uriList.add(Uri.parse('memory:$key'));
   }
+  Map<String, String> sourceFiles = serializedData.toMemorySourceFiles();
+  sourceFiles.addAll(test.preserializedSourceFiles);
+  if (test.unserializedSourceFiles != null) {
+    sourceFiles.addAll(test.unserializedSourceFiles);
+  }
   Compiler compiler = compilerFor(
-      memorySourceFiles:
-          serializedData.toMemorySourceFiles(test.preserializedSourceFiles),
+      memorySourceFiles: sourceFiles,
       resolutionInputs: serializedData.toUris(),
       options: [Flags.analyzeOnly, Flags.analyzeMain]);
   compiler.librariesToAnalyzeWhenRun = uriList;
   compiler.serialization.supportSerialization = true;
   await compiler.run(null);
   List<LibraryElement> libraries = <LibraryElement>[];
   for (Uri uri in uriList) {
     libraries.add(compiler.libraryLoader.lookupLibrary(uri));
   }
   SerializedData additionalSerializedData =
       new SerializedData(Uri.parse('memory:additional.data'),
       extractSerializedData(compiler, libraries));
   return <SerializedData>[serializedData, additionalSerializedData];
 }