Replace the configuration map with a typed object.

tools/testing/dart/http_server.dart

 // Copyright (c) 2013, 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 http_server;
-
 import 'dart:async';
+import 'dart:convert' show HtmlEscape;
 import 'dart:io';
 
-import 'dart:convert' show HtmlEscape;
+import 'package:package_resolver/package_resolver.dart';
 
-import 'test_suite.dart'; // For TestUtils.
+import 'configuration.dart';
+import 'test_suite.dart';
 import 'vendored_pkg/args/args.dart';
 import 'utils.dart';
-import 'package:package_resolver/package_resolver.dart';
 
 class DispatchingServer {
   HttpServer server;
   Map<String, Function> _handlers = new Map<String, Function>();
   Function _notFound;
 
   DispatchingServer(
       this.server, void onError(e), void this._notFound(HttpRequest request)) {
     server.listen(_dispatchRequest, onError: onError);
   }
@@ skipping 61 matching lines @@
   parser.addOption('runtime',
       help: 'The runtime we are using (for csp flags).', defaultsTo: 'none');
 
   var args = parser.parse(arguments);
   if (args['help'] as bool) {
     print(parser.getUsage());
   } else {
     var servers = new TestingServers(
         args['build-directory'] as String,
         args['csp'] as bool,
-        args['runtime'] as String,
+        Runtime.find(args['runtime'] as String),
         null,
         args['package-root'] as String,
         args['packages'] as String);
     var port = int.parse(args['port'] as String);
     var crossOriginPort = int.parse(args['crossOriginPort'] as String);
     servers
         .startServers(args['network'] as String,
             port: port, crossOriginPort: crossOriginPort)
         .then((_) {
       DebugLogger.info('Server listening on port ${servers.port}');
@@ skipping 17 matching lines @@
     "/NonExistingFile",
     "IntentionallyMissingFile",
   ];
 
   final List<HttpServer> _serverList = [];
   Uri _buildDirectory;
   Uri _dartDirectory;
   Uri _packageRoot;
   Uri _packages;
   final bool useContentSecurityPolicy;
-  final String runtime;
+  final Runtime runtime;
   DispatchingServer _server;
   SyncPackageResolver _resolver;
 
   TestingServers(String buildDirectory, this.useContentSecurityPolicy,
-      [String this.runtime = 'none',
+      [this.runtime = Runtime.none,
       String dartDirectory,
       String packageRoot,
       String packages]) {
     _buildDirectory = Uri.base.resolveUri(new Uri.directory(buildDirectory));
     if (dartDirectory == null) {
       _dartDirectory = TestUtils.dartDirUri;
     } else {
       _dartDirectory = Uri.base.resolveUri(new Uri.directory(dartDirectory));
     }
     if (packageRoot == null) {
@@ skipping 36 matching lines @@
     var script = _dartDirectory.resolve('tools/testing/dart/http_server.dart');
     var buildDirectory = _buildDirectory.toFilePath();
     var command = [
       dart,
       script.toFilePath(),
       '-p',
       port,
       '-c',
       crossOriginPort,
       '--build-directory=$buildDirectory',
-      '--runtime=$runtime'
+      '--runtime=${runtime.name}'
     ];
     if (useContentSecurityPolicy) {
       command.add('--csp');
     }
     if (_packages != null) {
       command.add('--packages=${_packages.toFilePath()}');
     } else if (_packageRoot != null) {
       command.add('--package-root=${_packageRoot.toFilePath()}');
     }
     return command.join(' ');
@@ skipping 262 matching lines @@
 class _Entry implements Comparable<_Entry> {
   final String name;
   final String displayName;
 
   _Entry(this.name, this.displayName);
 
   int compareTo(_Entry other) {
     return name.compareTo(other.name);
   }
 }