They are making an exception for tabs that are playing audio.

You can see the discussion back and forth, here: https://groups.google.com/a/chromium.org/forum/#!topic/blink...

I can see where that will end up though. Everyone who's app was broken by this change will start playing zero volume audio, then the exception will be yanked back.

With the web poised to be the new platform for applications, there really needs to be some more thought put into how to accomplish that goal. The chrome devs already sunset some solutions in that space, like the HTML5 app cache. Now this. Nobody likes a constantly moving target.