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tests/compiler/dart2js/type_promotion_test.dart

Index: tests/compiler/dart2js/type_promotion_test.dart
diff --git a/tests/compiler/dart2js/type_promotion_test.dart b/tests/compiler/dart2js/type_promotion_test.dart
index 37f77c9748b472c16735f2752b76a4c308d83b3b..b7b7cf087f96eaebb0a61b299ea7729ba3bad0c6 100644
--- a/tests/compiler/dart2js/type_promotion_test.dart
+++ b/tests/compiler/dart2js/type_promotion_test.dart
@@ -14,6 +14,7 @@ import '../../../sdk/lib/_internal/compiler/implementation/filenames.dart';
 import '../../../sdk/lib/_internal/compiler/implementation/source_file.dart';
 import '../../../sdk/lib/_internal/compiler/implementation/source_file_provider.dart';
 import '../../../sdk/lib/_internal/compiler/implementation/util/uri_extras.dart';
+import 'dart:convert';
 
 const List<String> TESTS = const [
     'language/type_promotion_assign_test.dart',
@@ -32,8 +33,8 @@ void main() {
   bool warningsMismatch = false;
   Future.forEach(TESTS, (String test) {
     Uri uri = script.resolve('../../$test');
-    String source = readAll(uriPathToNative(uri.path));
-    SourceFile file = new SourceFile(
+    String source = UTF8.decode(readAll(uriPathToNative(uri.path)));
+    SourceFile file = new StringSourceFile(
         relativize(currentDirectory, uri, isWindows), source);
     Map<int,String> expectedWarnings = {};
     int lineNo = 0;