Add a ScheduledProcess class to pkg/scheduled_test.

pkg/scheduled_test/lib/scheduled_test.dart

Index: pkg/scheduled_test/lib/scheduled_test.dart
diff --git a/pkg/scheduled_test/lib/scheduled_test.dart b/pkg/scheduled_test/lib/scheduled_test.dart
index 587abb7401dcdf4ec32801e8dfff2e6a514d2923..6ae8449c56b0b626b760af07c7417ebc493f9221 100644
--- a/pkg/scheduled_test/lib/scheduled_test.dart
+++ b/pkg/scheduled_test/lib/scheduled_test.dart
@@ -181,12 +181,13 @@ import 'src/schedule.dart';
 import 'src/schedule_error.dart';
 import 'src/utils.dart';
 
-export 'package:unittest/matcher.dart';
+export 'package:unittest/matcher.dart' hide completes, completion;
 export 'package:unittest/unittest.dart' show
     config, configure, Configuration, logMessage, expectThrow;
 
 export 'src/schedule.dart';
 export 'src/schedule_error.dart';
+export 'src/scheduled_future_matchers.dart';
 export 'src/task.dart';
 
 /// The [Schedule] for the current test. This is used to add new tasks and