Yep, Chrome broke all games published in 2012. We filed a bug report with them and they declined to fix it. There's more details in that thread. Long story short all that old content needs to be re-published, which affects all web content, not just our own arcade.
Our Arcade is in need of some upgrade work and we have it planned, and largely because of this I think we will require all games to be re-submitted when we relaunch it.