Warning should be shown when addEventListener is called after the very first evaluation of the service worker script.

Where firing the warning is here: https://cs.chromium.org/chromium/src/third_party/WebKit/Source/modules/serviceworkers/ServiceWorkerGlobalScope.cpp?dr=CSs&q=ServiceWorkerGlobalScope&sq=package:chromium&l=155

However, currently these messages are shown only on chrome://serviceworker-internals, and we cannot see them on DevTools. I've already confirmed ServiceWorkerContextWatcher::OnReportConsoleMessage and ServiceWorkerHandler::OnErrorReported were called correctly, so something seems wrong after that.