CONSOLE WARNING: Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience. For more help, check http://xhr.spec.whatwg.org/.
Test a simple offline application self-update process. Should print a series of messages followed with DONE:

Updating cache group...
Cache status is UPDATEREADY
Updating cache group once more...
Cache status is UPDATEREADY
Associating document with the newest cache version...
Cache status is IDLE
DONE