Improves how to initialize polymer apps and fixes polymer build and linter to

samples/third_party/todomvc/test/markdone_test.dart

Index: samples/third_party/todomvc/test/markdone_test.dart
diff --git a/samples/third_party/todomvc/test/markdone_test.dart b/samples/third_party/todomvc/test/markdone_test.dart
index c967767368c51f02224aa3b84f8c95d6f4d63469..e7a7989def3e3d9f9f87275274d816829b74d957 100644
--- a/samples/third_party/todomvc/test/markdone_test.dart
+++ b/samples/third_party/todomvc/test/markdone_test.dart
@@ -4,6 +4,7 @@
 
 library todomvc.test.markdone_test;
 
+import 'dart:async';
 import 'dart:html';
 import 'package:polymer/platform.dart' show endOfMicrotask;
 import 'package:polymer/polymer.dart';
@@ -47,7 +48,8 @@ Node findShadowHost(Node node, ShadowRoot root) {
  * This test runs the TodoMVC app, adds a few todos, marks some as done
  * programatically, and clicks on a checkbox to mark others via the UI.
  */
-@initMethod init() {
+main() {
+  initPolymer();
   useHtmlConfiguration();
 
   setUp(() => Polymer.onReady);