Fixing up measurement test.

lib/html/src/dart2js_MutationObserverSupported.dart

Index: lib/html/src/dart2js_MutationObserverSupported.dart
diff --git a/pkg/intl/example/basic/basic_example_runner.dart b/lib/html/src/dart2js_MutationObserverSupported.dart
similarity index 51%
copy from pkg/intl/example/basic/basic_example_runner.dart
copy to lib/html/src/dart2js_MutationObserverSupported.dart
index 004a5b286dc54401697cc3e6b92ac627594399e7..f7329073a696981376d34b9dbeadd0132765a700 100644
--- a/pkg/intl/example/basic/basic_example_runner.dart
+++ b/lib/html/src/dart2js_MutationObserverSupported.dart
@@ -3,12 +3,9 @@
 // BSD-style license that can be found in the LICENSE file.
 
 /**
- * This is just a shell that runs the code in basic_example.dart, leaving
- * that as a library that can also be run by tests.
+ * Checks to see if the mutation observer API is supported on the current
+ * platform.
  */
-
-#import('basic_example.dart');
-
-main() {
-  setup(runProgram, print);
-}
+bool _isMutationObserverSupported() native '''
+  return !!( window.MutationObserver || window.WebKitMutationObserver);
+''';