Better configure the Chrome launcher.

lib/src/runner/browser/chrome.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.
 
 library unittest.runner.browser.chrome;
 
 import 'dart:async';
 import 'dart:io';
 
+import 'package:path/path.dart' as p;
+
 import '../../util/io.dart';
 
 // TODO(nweiz): move this into its own package?
 // TODO(nweiz): support other browsers.
 /// A class for running an instance of Chrome.
 ///
 /// Most of the communication with the browser is expected to happen via HTTP,
 /// so this exposes a bare-bones API. The browser starts as soon as the class is
 /// constructed, and is killed when [close] is called.
 ///
@@ skipping 18 matching lines @@
   /// A future that completes when the browser process has started.
   ///
   /// This is used to ensure that [close] works regardless of when it's called.
   Future get _onProcessStarted => _onProcessStartedCompleter.future;
   final _onProcessStartedCompleter = new Completer();
 
   /// Starts a new instance of Chrome open to the given [url], which may be a
   /// [Uri] or a [String].
   ///
   /// If [executable] is passed, it's used as the Chrome executable. Otherwise
-  /// `"google-chrome"` will be looked up on the system PATH.
+  /// the default executable name for the current OS will be used.
   Chrome(url, {String executable}) {
-    if (executable == null) executable = "google-chrome";
+    if (executable == null) executable = _defaultExecutable();
 
     // Don't return a Future here because there's no need for the caller to wait
     // for the process to actually start. They should just wait for the HTTP
     // request instead.
     withTempDir((dir) {
       _dir = dir;
       return Process.start(executable, [
         "--user-data-dir=$_dir",
         url.toString(),
         "--disable-extensions",
         "--disable-popup-blocking",
         "--bwsi",
-        "--no-first-run"
+        "--no-first-run",
+        "--no-default-browser-check",
+        "--disable-default-apps",
+        "--disable-translate"
       ]).then((process) {
         _process = process;
         _onProcessStartedCompleter.complete();
 
         // TODO(nweiz): the browser's standard output is almost always useless
         // noise, but we should allow the user to opt in to seeing it.
         return _process.exitCode;
       });
     }).then((exitCode) {
       if (exitCode != 0) throw "Chrome failed with exit code $exitCode.";
     }).then(_onExitCompleter.complete)
         .catchError(_onExitCompleter.completeError);
   }
 
   /// Kills the browser process.
   ///
   /// Returns the same [Future] as [onExit], except that it won't emit
   /// exceptions.
   Future close() {
     _onProcessStarted.then((_) => _process.kill());
 
     // Swallow exceptions. The user should explicitly use [onExit] for these.
     return onExit.catchError((_) {});
   }
+
+  /// Return the default executable for the current operating system.
+  String _defaultExecutable() {
+    if (Platform.isMacOS) {
+      return '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome';
+    }
+    if (!Platform.isWindows) return 'google-chrome';
+
+    // Chrome could be installed in several places on Windows. The only way to
+    // find it is to check.
+    var prefixes = [
+      Platform.environment['LOCALAPPDATA'],
+      Platform.environment['PROGRAMFILES'],
+      Platform.environment['PROGRAMFILES(X86)']
+    ];
+    var suffix = r'Google\Chrome\Application\chrome.exe';
+
+    for (var prefix in prefixes) {
+      if (prefix == null) continue;
+
+      var path = p.join(prefix, suffix);
+      if (new File(p.join(prefix, suffix)).existsSync()) return path;
+    }
+
+    // Fall back on looking it up on the path. This probably won't work, but at
+    // least it will fail with a useful error message.
+    return "chrome.exe";
+  }
 }