Remove invalid sanity check.

utils/tests/pub/test_pub.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.
 
 /// Test infrastructure for testing pub. Unlike typical unit tests, most pub
 /// tests are integration tests that stage some stuff on the file system, run
 /// pub, and then validate the results. This library provides an API to build
 /// tests like that.
 library test_pub;
 
@@ skipping 444 matching lines @@
 bool _abortScheduled = false;
 
 /// The time (in milliseconds) to wait for the entire scheduled test to
 /// complete.
 final _TIMEOUT = 30000;
 
 /// Defines an integration test. The [body] should schedule a series of
 /// operations which will be run asynchronously.
 void integration(String description, void body()) {
   test(description, () {
-    // Sanity check. Make sure we cleaned up the last test.
-    assert(_scheduled == null);
-    assert(_scheduledCleanup == null);
-    assert(_scheduledOnException == null);
-
     // Schedule the test.
     body();
 
     // Run all of the scheduled tasks. If an error occurs, it will propagate
     // through the futures back up to here where we can hand it off to unittest.
     var asyncDone = expectAsync0(() {});
     var createdSandboxDir;
     _setUpSandbox().then((sandboxDir) {
       createdSandboxDir = sandboxDir;
       return timeout(_runScheduled(sandboxDir, _scheduled),
@@ skipping 1075 matching lines @@
 /// calling [completion] is unnecessary.
 void expectLater(Future actual, matcher, {String reason,
     FailureHandler failureHandler, bool verbose: false}) {
   _schedule((_) {
     return actual.then((value) {
       expect(value, matcher, reason: reason, failureHandler: failureHandler,
           verbose: false);
     });
   });
 }