pkg/isolate: library renaming, removed unused method, fix creation of TimeoutException

lib/load_balancer.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.
 
 /// A load-balancing runner pool.
-library dart.pkg.isolate.loadbalancer;
+library isolate.load_balancer;
 
-import "runner.dart";
-import "src/errors.dart";
-import "src/lists.dart";
-import "dart:async" show Future;
+import 'dart:async' show Future;
+
+import 'runner.dart';
+import 'src/errors.dart';
+import 'src/lists.dart';
 
 /// A pool of runners, ordered by load.
 ///
 /// Keeps a pool of runners,
 /// and allows running function through the runner with the lowest current load.
 class LoadBalancer implements Runner {
   // A heap-based priority queue of entries, prioritized by `load`.
   // Each entry has its own entry in the queue, for faster update.
   List<_LoadBalancerEntry> _queue;
 
@@ skipping 249 matching lines @@
     return runner.run(function, argument,
                       timeout: timeout, onTimeout: onTimeout).whenComplete(() {
       balancer._decreaseLoad(this, load);
     });
   }
 
   Future close() => runner.close();
 
   int compareTo(_LoadBalancerEntry other) => load - other.load;
 }