Fix for Animation and other polyfills

pkg/dev_compiler/test/browser/language_tests.js

Index: pkg/dev_compiler/test/browser/language_tests.js
diff --git a/pkg/dev_compiler/test/browser/language_tests.js b/pkg/dev_compiler/test/browser/language_tests.js
index d7222dc4d9b2db71f05107c622a36abc632607b3..8292e931903ea2761479833a0e393ec181d613e9 100644
--- a/pkg/dev_compiler/test/browser/language_tests.js
+++ b/pkg/dev_compiler/test/browser/language_tests.js
@@ -45,7 +45,7 @@ define(['dart_sdk', 'async_helper', 'expect', 'unittest', 'is', 'require'],
 
   // The number of expected unittest errors should be zero but unfortunately
   // there are a lot of broken html unittests.
-  let num_expected_unittest_fails = 3;
+  let num_expected_unittest_fails = 4;

[vsm, 2017/01/21 00:52:42]

This is due to: https://github.com/dart-lang/sdk/issues/26730
The other tests pass.

   let num_expected_unittest_errors = 0;
 
   // TODO(jmesserly): separate StrongModeError from other errors.
@@ -390,7 +390,7 @@ define(['dart_sdk', 'async_helper', 'expect', 'unittest', 'is', 'require'],
       // was https://github.com/dart-lang/sdk/issues/27578, needs triage
       'dom_constructors_test': 'fail',
 
-      'element_animate_test': async_unittest,
+      'element_animate_test': 'unittest',
 
       // https://github.com/dart-lang/sdk/issues/27579.
       'element_classes_test': 'fail',