Eagerly close browser tests.

lib/src/runner/loader.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:io';
 import 'dart:isolate';
 
 import 'package:analyzer/analyzer.dart' hide Configuration;
 import 'package:async/async.dart';
@@ skipping 242 matching lines @@
   /// Deserializes [test] into a concrete [Test] class.
   ///
   /// Returns `null` if [test] is `null`.
   Test _deserializeTest(Map test) {
     if (test == null) return null;
 
     var metadata = new Metadata.deserialize(test['metadata']);
     return new IsolateTest(test['name'], metadata, test['sendPort']);
   }
 
+  /// Close all the browsers that the loader currently has open.
+  ///
+  /// Note that this doesn't close the loader itself. Browser tests can still be
+  /// loaded, they'll just spawn new browsers.
+  Future closeBrowsers() async {
+    if (!_browserServerMemo.hasRun) return;
+    await (await _browserServer).closeBrowsers();
+  }
+
   /// Closes the loader and releases all resources allocated by it.
   Future close() {
     return _closeMemo.runOnce(() async {
       await Future.wait(_suites.map((suite) => suite.close()));
       _suites.clear();
 
       if (!_browserServerMemo.hasRun) return;
       await (await _browserServer).close();
     });
   }
 }