fix parsing of semantic template interation w/ shadowdom polyfill

pkg/mdv/test/mdv_test_utils.dart

Index: pkg/mdv/test/mdv_test_utils.dart
diff --git a/pkg/mdv/test/mdv_test_utils.dart b/pkg/mdv/test/mdv_test_utils.dart
index e055824b089457e180f7c306e32c69659d8f16b0..4b01d7fb319566130df2c2a009f903bce8e439f2 100644
--- a/pkg/mdv/test/mdv_test_utils.dart
+++ b/pkg/mdv/test/mdv_test_utils.dart
@@ -5,9 +5,16 @@
 library observe_utils;
 
 import 'dart:async';
+import 'dart:html';
 import 'package:observe/observe.dart';
 import 'package:unittest/unittest.dart';
 
+final bool parserHasNativeTemplate = () {
+  var div = new DivElement()..innerHtml = '<table><template>';
+  return div.firstChild.firstChild != null &&
+      div.firstChild.firstChild.tagName == 'TEMPLATE';
+}();
+
 toSymbolMap(Map map) {
   var result = new ObservableMap.linked();
   map.forEach((key, value) {