Handle explicit constructor.

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 12 matching lines @@
 import 'package:compiler/src/serialization/resolved_ast_serialization.dart';
 import 'package:compiler/src/serialization/serialization.dart';
 import 'package:compiler/src/serialization/system.dart';
 import 'package:compiler/src/serialization/task.dart';
 import 'package:compiler/src/tokens/token.dart';
 import 'package:compiler/src/universe/call_structure.dart';
 import 'package:compiler/src/universe/world_impact.dart';
 import 'package:compiler/src/universe/use.dart';
 
 import '../memory_compiler.dart';
+import 'test_data.dart';
 
 class Arguments {
   final String filename;
-  final int index;
+  final int start;
+  final int end;
   final bool loadSerializedData;
   final bool saveSerializedData;
   final String serializedDataFileName;
   final bool verbose;
 
   const Arguments({
     this.filename,
-    this.index,
+    this.start,
+    this.end,
     this.loadSerializedData: false,
     this.saveSerializedData: false,
     this.serializedDataFileName: 'out.data',
     this.verbose: false});
 
   factory Arguments.from(List<String> arguments) {
     String filename;
-    int index;
+    int start;
+    int end;
     for (String arg in arguments) {
       if (!arg.startsWith('-')) {
-        index = int.parse(arg);
+        int index = int.parse(arg);
         if (index == null) {
           filename = arg;
+        } else if (start == null) {
+          start = index;
+        } else {
+          end = index;
         }
       }
     }
     bool verbose = arguments.contains('-v');
     bool loadSerializedData = arguments.contains('-l');
     bool saveSerializedData = arguments.contains('-s');
     return new Arguments(
         filename: filename,
-        index: index,
+        start: start,
+        end: end,
         verbose: verbose,
         loadSerializedData: loadSerializedData,
         saveSerializedData: saveSerializedData);
   }
+
+  Future forEachTest(List<Test> tests, Future f(int index, Test test)) async {
+    int first = start ?? 0;
+    int last = end ?? tests.length - 1;
+    for (int index = first; index <= last; index++) {
+      Test test = TESTS[index];
+      await f(index, test);
+    }
+  }
 }
 
 
 Future<String> serializeDartCore(
     {Arguments arguments: const Arguments()}) async {
   print('------------------------------------------------------------------');
   print('serialize dart:core');
   print('------------------------------------------------------------------');
   String serializedData;
   if (arguments.loadSerializedData) {
@@ skipping 13 matching lines @@
         sink, compiler.libraryLoader.libraries);
     serializedData = sink.text;
     if (arguments.saveSerializedData) {
       File file = new File(arguments.serializedDataFileName);
       print('Saving data to $file');
       file.writeAsStringSync(serializedData);
     }
   }
   return serializedData;
 }