There's no simple, cross-platform way to register protocol handlers in Electron. Every OS requires a different solution. This seems like something that Electron should smooth over.

There's already a W3C API for this: [`Navigator.registerProtocolHandler`](https://developer.mozilla.org/en-US/docs/Web/API/Navigator/registerProtocolHandler). Can Electron implement it?

atom/browser/api/atom_api_app.cc
v8::Isolate* isolate,
    std::shared_ptr<content::ClientCertificateDelegate> delegate,
    mate::Arguments* args) {
  mate::Dictionary cert_data;
  if (!args->GetNext(&cert_data)) {
    args->ThrowError();
    return;
  }
  v8::Local<v8::Object> data;
  if (!cert_data.Get("data", &data))
    return;
  auto certs = net::X509Certificate::CreateCertificateListFromBytes(
      node::Buffer::Data(data), node::Buffer::Length(data),
      net::X509Certificate::FORMAT_AUTO);
  if (certs.size() > 0)
    delegate->ContinueWithCertificate(certs[0].get());
}
void PassLoginInformation(scoped_refptr<LoginHandler> login_handler,
                          mate::Arguments* args) {
  base::string16 username, password;
  if (args->GetNext(&username) && args->GetNext(&password))
    login_handler->Login(username, password);
  else
    login_handler->CancelAuth();
}
}  
App::App() {