Add support for --dart2js-path and --dart2js-args.

lib/src/runner/browser/compiler_pool.dart

 // Copyright (c) 2015, 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.
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
 import 'package:async/async.dart';
 import 'package:path/path.dart' as p;
 import 'package:pool/pool.dart';
 
 import '../../util/io.dart';
+import '../configuration.dart';
 import '../load_exception.dart';
 
 /// A pool of `dart2js` instances.
 ///
 /// This limits the number of compiler instances running concurrently.
 class CompilerPool {
   /// The internal pool that controls the number of process running at once.
   final Pool _pool;
 
-  /// Whether to enable colors on dart2js.
-  final bool _color;
+  /// The test runner configuration.
+  final Configuration _config;
 
   /// The currently-active dart2js processes.
   final _processes = new Set<Process>();
 
   /// Whether [close] has been called.
   bool get _closed => _closeMemo.hasRun;
 
   /// The memoizer for running [close] exactly once.
   final _closeMemo = new AsyncMemoizer();
 
-  /// Creates a compiler pool that runs up to [concurrency] instances of
-  /// `dart2js` at once.
-  ///
-  /// If [concurrency] isn't provided, it defaults to 4.
-  ///
-  /// If [color] is true, `dart2js` will be run with colors enabled.
-  CompilerPool({int concurrency, bool color: false})
-      : _pool = new Pool(concurrency == null ? 4 : concurrency),
-        _color = color;
+  /// Creates a compiler pool that multiple instances of `dart2js` at once.
+  CompilerPool(Configuration config)
+      : _pool = new Pool(config.concurrency),
+        _config = config;
 
   /// Compile the Dart code at [dartPath] to [jsPath].
   ///
   /// This wraps the Dart code in the standard browser-testing wrapper. If
   /// [packageRoot] is provided, it's used as the package root for the
   /// compilation.
   ///
   /// The returned [Future] will complete once the `dart2js` process completes
   /// *and* all its output has been printed to the command line.
   Future compile(String dartPath, String jsPath, {String packageRoot}) {
     return _pool.withResource(() {
       if (_closed) return null;
 
       return withTempDir((dir) async {
         var wrapperPath = p.join(dir, "runInBrowser.dart");
         new File(wrapperPath).writeAsStringSync('''
           import "package:stream_channel/stream_channel.dart";
 
           import "package:test/src/runner/plugin/remote_platform_helpers.dart";
           import "package:test/src/runner/browser/post_message_channel.dart";
 
           import "${p.toUri(p.absolute(dartPath))}" as test;
 
           main(_) async {
             var channel = serializeSuite(() => test.main, hidePrints: false);
             postMessageChannel().pipe(channel);
           }
         ''');
 
-        var dart2jsPath = p.join(sdkDir, 'bin', 'dart2js');
+        var dart2jsPath = _config.dart2jsPath;
         if (Platform.isWindows) dart2jsPath += '.bat';
 
-        var args = ["--checked", wrapperPath, "--out=$jsPath"];
+        var args = ["--checked", wrapperPath, "--out=$jsPath"]
+          ..addAll(_config.dart2jsArgs);
 
         if (packageRoot != null) {
           args.add("--package-root=${p.toUri(p.absolute(packageRoot))}");
         }
 
-        if (_color) args.add("--enable-diagnostic-colors");
+        if (_config.color) args.add("--enable-diagnostic-colors");
 
         var process = await Process.start(dart2jsPath, args);
         if (_closed) {
           process.kill();
           return;
         }
 
         _processes.add(process);
 
         /// Wait until the process is entirely done to print out any output.
@@ skipping 52 matching lines @@
   /// have been killed and all resources released.
   Future close() {
     return _closeMemo.runOnce(() async {
       await Future.wait(_processes.map((process) async {
         process.kill();
         await process.exitCode;
       }));
     });
   }
 }