* **Electron Version** (output of `node_modules/.bin/electron --version`):
  * 3.0.6
* **Operating System** (Platform and Version):
  * macOS 10.14

### Expected Behavior
a `new-window` event fires

### Actual behavior
a `did-fail-load` fires with errorCode -3

### To Reproduce
```sh
$ git clone git@github.com:chrismohr/no-new-window.git -b master
$ cd no-new-window/
$ npm i && npm start
```

atom/browser/atom_browser_client.cc
DCHECK_CURRENTLY_ON(BrowserThread::UI);
  DCHECK(g_browser_process->system_network_context_manager());
  return g_browser_process->system_network_context_manager()->GetContext();
}
void AtomBrowserClient::RegisterOutOfProcessServices(
    OutOfProcessServiceMap* services) {
  (*services)[proxy_resolver::mojom::kProxyResolverServiceName] =
      base::BindRepeating(&l10n_util::GetStringUTF16,
                          IDS_UTILITY_PROCESS_PROXY_RESOLVER_NAME);
#if BUILDFLAG(ENABLE_PRINTING)
  (*services)[printing::mojom::kServiceName] =
      base::BindRepeating(&l10n_util::GetStringUTF16,
                          IDS_UTILITY_PROCESS_PDF_COMPOSITOR_SERVICE_NAME);
  (*services)[printing::mojom::kChromePrintingServiceName] =
      base::BindRepeating(&l10n_util::GetStringUTF16,
                          IDS_UTILITY_PROCESS_PRINTING_SERVICE_NAME);
#endif
}
base::Optional<service_manager::Manifest>
AtomBrowserClient::GetServiceManifestOverlay(base::StringPiece name) {
  if (name == content::mojom::kBrowserServiceName) {
    return GetElectronContentBrowserOverlayManifest();
  } else if (name == content::mojom::kPackagedServicesServiceName) {
    service_manager::Manifest overlay;
    overlay.packaged_services = GetElectronPackagedServicesOverlayManifest();
    return overlay;
  }
  return base::nullopt;
}
net::NetLog* AtomBrowserClient::GetNetLog() {