JetBrains: update JCEF when settings change
Created by: vdavid
Fixes https://github.com/sourcegraph/sourcegraph/issues/36537
Notes:
- It uses the message bus.
- I've also extracted "getConfigAsJson" to ConfigUtil
- I've also made sure that the new listener connection is disposed of with the service.
- Made JavaToJSBridge pool use two queries, to make sure settings change can be applied at the same time as the theme change. It's because IF you change the theme from light to dark AND change plugin settings, then these need to be applied simultaneously when you press "OK" in Settings.
Test plan
App preview:
Check out the client app preview documentation to learn more.