update polymer js to 0.4.0

pkg/template_binding/test/template_binding_test.dart

Index: pkg/template_binding/test/template_binding_test.dart
diff --git a/pkg/template_binding/test/template_binding_test.dart b/pkg/template_binding/test/template_binding_test.dart
index de7e8c37af7f783668f6f50f0c25fa84ef6a87c0..fde463b55f6e83d9d4a4b1a6e674dc9a9b01e20d 100644
--- a/pkg/template_binding/test/template_binding_test.dart
+++ b/pkg/template_binding/test/template_binding_test.dart
@@ -1369,14 +1369,22 @@ templateInstantiationTests() {
       expect(div.nodes.length, 4);
       expect('Hi, Fry', div.nodes[3].text);
 
-      div.nodes[2].attributes['ref'] = 'B';
+      // In IE 11, MutationObservers do not fire before setTimeout.
+      // So rather than using "then" to queue up the next test, we use a
+      // MutationObserver here to detect the change to "ref".

[Siggi Cherem (dart-lang), 2014/09/09 21:21:43]

what if we use endOfMicrotask instead? or is that too soon?

[jakemac, 2014/09/10 16:30:00]

I think its best to keep this in sync with the js side, it sounds like they were
having issues with their version of endOfMicrotask so that is why they changed
it here.

+      var done = new Completer();
+      new MutationObserver((mutations, observer) {
+        expect(div.nodes.length, 5);
+
+        expect('Hola, Fry', div.nodes[3].text);
+        expect('Hola, Leela', div.nodes[4].text);
+        done.complete();
+      }).observe(template, attributes: true, attributeFilter: ['ref']);
+
+      template.setAttribute('ref', 'B');
       model.add('Leela');
 
-    }).then(nextMicrotask).then((x) {
-      expect(div.nodes.length, 5);
-
-      expect('Hola, Fry', div.nodes[3].text);
-      expect('Hola, Leela', div.nodes[4].text);
+      return done.future;
     });
   });