Since #19488, the network service is enabled and the old path has been deleted. Some features are broken as a result and will need to be fixed before 8.0.0. This is a tracking issue for those features.

- [x] webRequest API (zcbenz)
- [x] service workers on file protocol (#20132)
- [x] session.clearAuthCache - tests (#20015)
- [x] session.getBlobData (#20041)
- [x] session.setUserAgent (#20014)
- [x] custom standard schemes / registerSchemesAsPrivileged
- [x] Rewire Login Handler from NetworkDelegate into ProxyingURLLoaderFactory
- [x] fix 'login' event not firing on net requests

cc @deepak1556 @jkleinsc @zcbenz 
shell/browser/api/atom_api_session.cc
mate::Arguments* args) {
  GURL url;
  if (!options.Get("url", &url) || !url.is_valid()) {
    args->ThrowError("Must pass non-empty valid url to session.preconnect.");
    return;
  }
  int num_sockets_to_preconnect = 1;
  if (options.Get("numSockets", &num_sockets_to_preconnect)) {
    const int kMinSocketsToPreconnect = 1;
    const int kMaxSocketsToPreconnect = 6;
    if (num_sockets_to_preconnect < kMinSocketsToPreconnect ||
        num_sockets_to_preconnect > kMaxSocketsToPreconnect) {
      args->ThrowError(
          base::StringPrintf("numSocketsToPreconnect is outside range [%d,%d]",
                             kMinSocketsToPreconnect, kMaxSocketsToPreconnect));
      return;
    }
  }
  DCHECK_GT(num_sockets_to_preconnect, 0);
  base::PostTaskWithTraits(
      FROM_HERE, {content::BrowserThread::UI},
      base::BindOnce(&StartPreconnectOnUI, base::RetainedRef(browser_context_),
                     url, num_sockets_to_preconnect));
}
mate::Handle<Session> Session::CreateFrom(v8::Isolate* isolate,