Update: Great news! After doing some more digging, it turns out this feature is already in the latest Canary build of Google Chrome (not Chromium). Furthermore, it works on Flash sites, confirming support for plugins is actively being developed. (via Google Chrome may soon get audio indicators to show you noisy tabs, keep them open when memory runs out (Updated) - The Next Web)

Update: Great news! After doing some more digging, it turns out this feature is already in the latest Canary build of Google Chrome (not Chromium). Furthermore, it works on Flash sites, confirming support for plugins is actively being developed. (via Google Chrome may soon get audio indicators to show you noisy tabs, keep them open when memory runs out (Updated) - The Next Web)