Add firefox support.

test/runner/browser/runner_test.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.
 
 @TestOn("vm")
 
 import 'dart:io';
 
 import 'package:path/path.dart' as p;
 import 'package:test/src/util/exit_codes.dart' as exit_codes;
@@ skipping 78 matching lines @@
           'Failed to load "${p.relative(testPath, from: _sandbox)}": Top-level '
               'main() function takes arguments.\n'));
       expect(result.exitCode, equals(exit_codes.data));
     });
 
     // TODO(nweiz): test what happens when a test file is unreadable once issue
     // 15078 is fixed.
   });
 
   group("runs successful tests", () {
-    test("on the browser only", () {
+    test("on Chrome", () {
       new File(p.join(_sandbox, "test.dart")).writeAsStringSync(_success);
       var result = _runUnittest(["-p", "chrome", "test.dart"]);
       expect(result.exitCode, equals(0));
     });
 
+    test("on Firefox", () {
+      new File(p.join(_sandbox, "test.dart")).writeAsStringSync(_success);
+      var result = _runUnittest(["-p", "firefox", "test.dart"]);
+      expect(result.exitCode, equals(0));
+    });
+
+    test("on multiple browsers", () {
+      new File(p.join(_sandbox, "test.dart")).writeAsStringSync(_success);
+      var result = _runUnittest(["-p", "firefox", "-p", "chrome", "test.dart"]);
+      expect("Compiling".allMatches(result.stdout), hasLength(1));
+      expect(result.exitCode, equals(0));
+    });
+
     test("on the browser and the VM", () {
       new File(p.join(_sandbox, "test.dart")).writeAsStringSync(_success);
       var result = _runUnittest(["-p", "chrome", "-p", "vm", "test.dart"]);
       expect(result.exitCode, equals(0));
     });
   });
 
   group("runs failing tests", () {
-    test("on the browser only", () {
+    test("on Chrome", () {
       new File(p.join(_sandbox, "test.dart")).writeAsStringSync("""
 import 'dart:async';
 
 import 'package:test/test.dart';
 
 void main() {
   test("failure", () => throw new TestFailure("oh no"));
 }
 """);
       var result = _runUnittest(["-p", "chrome", "test.dart"]);
       expect(result.exitCode, equals(1));
     });
 
+    test("on Firefox", () {
+      new File(p.join(_sandbox, "test.dart")).writeAsStringSync("""
+import 'dart:async';
+
+import 'package:test/test.dart';
+
+void main() {
+  test("failure", () => throw new TestFailure("oh no"));
+}
+""");
+      var result = _runUnittest(["-p", "firefox", "test.dart"]);
+      expect(result.exitCode, equals(1));
+    });
+
     test("that fail only on the browser", () {
       new File(p.join(_sandbox, "test.dart")).writeAsStringSync("""
 import 'dart:async';
 
 import 'package:path/path.dart' as p;
 import 'package:test/test.dart';
 
 void main() {
   test("test", () {
     if (p.style == p.Style.url) throw new TestFailure("oh no");
@@ skipping 37 matching lines @@
 """);
 
     var result = _runUnittest(["-p", "chrome", "test.dart"]);
     expect(result.stdout, contains("Hello,\nworld!\n"));
     expect(result.exitCode, equals(0));
   });
 }
 
 ProcessResult _runUnittest(List<String> args) =>
     runUnittest(args, workingDirectory: _sandbox);