Specify a way to know the bitness of the app

[mehagar]

Related: #217

There is a use case for having Chrome OS (as well as other user agents) reveal whether or not they are running on 32-bit browser, such as the difference between Chrome 32-bit OS or 64-bit Chrome OS. In the case of Chrome 32-bit OS, the CPU architecture itself is 64-bit, meaning the existing "arch" hint is insufficient.

The Zoom web app (app.zoom.us/wc) currently handles Windows 32-bit Chrome differently by changing how its WebAssembly memory is allocated. While Windows 32-bit Chrome exposes the "WoW64" user agent hint, Chrome OS does not currently. We frequently receive reports from users who experience issues when using the 32-bit version of Chrome OS, so it would be useful to detect that situation, both in terms of trying to avoid issues (such as allocating memory differently) as well as for troubleshooting, so we don't have to explicitly ask the user what OS version they are using each time.

[miketaylr]

While Windows 32-bit Chrome exposes the "WoW64" user agent hint, Chrome OS does not currently

Despite being named after a "Windows-ism" for "WoW64", it seems desirable to expose this scenario without any reference to any operating system, in hopes that all users have a decent user experience.