fix packages for latest SDK changes

pkg/observe/lib/src/microtask.dart

 // Copyright (c) 2013, 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.
 
-library observe.test.observe_test_utils;
+/**
+ * *Warning*: this library is **internal**, and APIs are subject to change.
+ *
+ * Wraps a callback using [wrapMicrotask] and provides the ability to pump all
+ * observable objects and [runAsync] calls via [performMicrotaskCheckpoint].
+ */
+library observe.src.microtask;
 
-import 'dart:async';
-import 'package:observe/observe.dart';
-import 'package:unittest/unittest.dart';
+import 'dart:async' show Completer, runZonedExperimental;
+import 'package:observe/observe.dart' show Observable;
 
-// TODO(jmesserly): use matchers when we have a way to compare ChangeRecords.
-// For now just use the toString.
-expectChanges(actual, expected, {reason}) =>
-    expect('$actual', '$expected', reason: reason);
+// TODO(jmesserly): remove "microtask" from these names and instead import
+// the library "as microtask"?
 
 /**
  * This change pumps events relevant to observers and data-binding tests.
  * This must be used inside an [observeTest].
  *
  * Executes all pending [runAsync] calls on the event loop, as well as
  * performing [Observable.dirtyCheck], until there are no more pending events.
  * It will always dirty check at least once.
  */
 void performMicrotaskCheckpoint() {
@@ skipping 25 matching lines @@
   return () {
     runZonedExperimental(() {
       try {
         testCase();
       } finally {
         performMicrotaskCheckpoint();
       }
     }, onRunAsync: (callback) => _pending.add(callback));
   };
 }
-
-/**
- * This is a special kind of unit [test], that supports
- * calling [performMicrotaskCheckpoint] during the test to pump events
- * that original from observable objects.
- */
-observeTest(name, testCase) => test(name, wrapMicrotask(testCase));
-
-/** The [solo_test] version of [observeTest]. */
-solo_observeTest(name, testCase) => solo_test(name, wrapMicrotask(testCase));