Move some core classes to collection library.

tools/testing/dart/test_runner.dart

 // Copyright (c) 2012, 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.
 
 /**
  * Classes and methods for executing tests.
  *
  * This module includes:
  * - Managing parallel execution of tests, including timeout checks.
  * - Evaluating the output of each test as pass/fail/crash/timeout.
  */
 library test_runner;
 
 import "dart:async";
+import "dart:collection" show Queue;
 // We need to use the 'io' prefix here, otherwise io.exitCode will shadow
 // CommandOutput.exitCode in subclasses of CommandOutput.
 import "dart:io" as io;
 import "dart:isolate";
 import "dart:uri";
 import "http_server.dart" as http_server;
 import "status_file_parser.dart";
 import "test_progress.dart";
 import "test_suite.dart";
 import "utils.dart";
@@ skipping 1721 matching lines @@
         // the developer doesn't waste his or her time trying to fix a bunch of
         // tests that appear to be broken but were actually just flakes that
         // didn't get retried because there had already been one failure.
         bool allowRetry = _MAX_FAILED_NO_RETRY > _progress.numFailedTests;
         new RunningProcess(test, allowRetry, this).start();
       }
       _numProcesses++;
     }
   }
 }