Reapply webkitRequestAimationFrame->requestAnimationFrame with fix for dartium

tests/html/callbacks_test.dart

Index: tests/html/callbacks_test.dart
===================================================================
--- tests/html/callbacks_test.dart	(revision 12823)
+++ tests/html/callbacks_test.dart	(working copy)
@@ -6,6 +6,6 @@
 main() {
   useHtmlConfiguration();
   test('RequestAnimationFrameCallback', () {
-    window.webkitRequestAnimationFrame((int time) => false);
+    window.requestAnimationFrame((int time) => false);

[blois, 2012/09/25 23:19:15]

This should cause this test to be passing on IE and FF, doesn't the status file
need updating?

   });
 }