While trying to register service worker from file:// protocol, I am getting the following error:

Failed to register a ServiceWorker: The URL protocol of the current origin ('file://') is not supported.

Code used to register service worker, as follows: (serviceworker.js is an empty file)

navigator.serviceWorker.register('./serviceworker.js')
.then(function(registration) {
    // succeeded
})
.catch(function(e) {
    // failed
});

I've tried to enable support for file:// protocol by calling blink::WebSecurityPolicy::registerURLSchemeAsAllowingServiceWorkers() with file protocol:

void ContentRendererClientQt::RenderFrameCreated(content::RenderFrame* render_frame)
{
    new QtWebEngineCore::RenderFrameObserverQt(render_frame);

    // code below has been added
    static const char kFileSchemeQt[] = "file";
    blink::WebString fileScheme(base::ASCIIToUTF16(kFileSchemeQt));
    blink::WebSecurityPolicy::registerURLSchemeAsAllowingServiceWorkers(fileScheme);
}

however, it gives me the following error.

Failed to register a ServiceWorker: A bad HTTP response code (-1) was received when fetching the script.

Did anyone try to enable service worker with success?