Unable to detect Chromium based browsers

Hi Team,

The code for isChromPackagedApp at line https://github.com/sockjs/sockjs-client/blob/50273185ca51649216e2e633a6dfdad42f497d98/dist/sockjs.js#L3279 does not seem to work as expected. It is not distinguishing between different browsers, as the last value (runtime) in the condition global.chrome.app.runtime is not existing.

Now that chromium based browsers planning to remove unload completely - https://developer.chrome.com/articles/deprecating-unload/ , there is a chance that some functionality might not work as desired.

Can someone please take a look?

Thanks in advance!!