move fancy_syntax into Dart SVN

pkg/polymer_expression/lib/async.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.
 
-// Test that deferred loading requires same library names.
+library polymer_expression.async;
 
 import 'dart:async';
+import 'package:observe/observe.dart';
 
-@lazy  /// 01: compile-time error
-import 'deferred_function_library.dart';
+class StreamBinding<T> extends ObservableBox {
+  final Stream<T> stream;
 
-const lazy = const DeferredLibrary('fisk');
+  StreamBinding(this.stream) {
+    stream.listen((T i) { value = i; });
+  }
 
-main() {
 }