Prevent the extension service workers idle timeout

[kaiser zhang]

Currently, Can be used runtime port(chrome.runtime.connect) for prevent the background into Inactive.

The connection runtime port idle timeout was 5 minutes mark of each time. 

demo: https://github.com/zhangkaiser/prevent-extension-background-inactive

[wOxxOm]

There are several workarounds to prolong the SW lifetime for more than 5 minutes in https://stackoverflow.com/a/66618269.