fixes for latest SDK

lib/polymer.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.
 
 /**
  * This library exports all of the commonly used functions and types for
  * building UI's.
  *
  * See this article for more information:
  * <http://www.dartlang.org/articles/dart-web-components/>.
  */
 library polymer;
 
 import 'dart:async';
 import 'dart:mirrors';
 
+import 'package:custom_element/custom_element.dart';
 import 'package:mdv/mdv.dart' as mdv;
 import 'package:observe/observe.dart' show Observable;
+import 'package:observe/src/microtask.dart';
 import 'package:path/path.dart' as path;
 import 'polymer_element.dart' show registerPolymerElement;
 
 export 'package:custom_element/custom_element.dart';
 export 'package:observe/observe.dart';
+export 'package:observe/src/microtask.dart';
 
 export 'event.dart';
 export 'observe.dart';
 export 'observe_html.dart';
 export 'polymer_element.dart';
 export 'safe_html.dart';
 export 'scoped_css.dart';
 
 
 /** Annotation used to automatically register polymer elements. */
@@ skipping 14 matching lines @@
  * each library in [elementLibraries], and finally invoking [userMain].
  *
  * There are two mechanisms by which custom elements can be initialized:
  * annotating the class that declares a custom element with [CustomTag] or
  * programatically registering the element in a static or top-level function and
  * annotating that function with [polymerInitMethod].
  *
  * The urls in [elementLibraries] can be absolute or relative to [srcUrl].
  */
 initPolymer(List<String> elementLibraries, void userMain(), [String srcUrl]) {
-  new Timer.periodic(new Duration(milliseconds: 125),
-      (_) => Observable.dirtyCheck());
+  wrapMicrotask(() {
+    // DOM events don't yet go through microtasks, so we catch those here.
+    new Timer.periodic(new Duration(milliseconds: 125),
+        (_) => performMicrotaskCheckpoint());
 
-  // TODO(jmesserly): mdv should use initMdv instead of mdv.initialize.
-  mdv.initialize();
-  for (var lib in elementLibraries) {
-    _registerPolymerElementsOf(lib, srcUrl);
-  }
-  userMain();
+    // TODO(jmesserly): mdv should use initMdv instead of mdv.initialize.
+    mdv.initialize();
+    for (var lib in elementLibraries) {
+      _registerPolymerElementsOf(lib, srcUrl);
+    }
+    userMain();
+  })();
 }
 
 /** All libraries in the current isolate. */
 var _libs = currentMirrorSystem().libraries;
 
 /**
  * Reads the library at [uriString] (which can be an absolute URI or a relative
  * URI from [srcUrl]), and:
  *
  *   * Invokes top-level and static functions marked with the
@@ skipping 55 matching lines @@
     print("warning: methods marked with @polymerInitMethod should take no "
         "arguments, ${method.simpleName} expects some.");
     return;
   }
   obj.invoke(method.simpleName, const []);
 }
 
 class _InitPolymerAnnotation {
   const _InitPolymerAnnotation();
 }