* Output of `node_modules/.bin/electron --version`: v4.0.0
* Operating System (Platform and Version): macOS 10.14.2

* Output of `node_modules/.bin/electron --version` on last known working Electron version (if applicable): 2.0.7

### Expected behavior

I should be able to call `app.setAccessibilitySupportEnabled(true)` during initialization, and the application should start and stay open.

### Actual behavior

The application starts and exits immediately if `app.setAccessibilitySupportEnabled(true)` is called during initialization. Same for passing in `false`.

### How to reproduce

Here is a simple project that shows this error. The application behaves as expected (does not exit immediately) when this line is commented out:
https://github.com/marisademeglio/electron4-setA11yTreeEnabled/blob/master/src/main/main.js#L27

  $ git clone https://github.com/marisademeglio/electron4-setA11yTreeEnabled.git
  $ yarn install
  $ yarn start

atom/browser/api/atom_api_app.cc
scoped_refptr<net::X509Certificate> cert,
                   scoped_refptr<net::SSLPrivateKey> private_key) {
  delegate->ContinueWithCertificate(cert, private_key);
}
void OnClientCertificateSelected(
    v8::Isolate* isolate,
    std::shared_ptr<content::ClientCertificateDelegate> delegate,
    std::shared_ptr<net::ClientCertIdentityList> identities,
    mate::Arguments* args) {
  if (args->Length() == 2) {
    delegate->ContinueWithCertificate(nullptr, nullptr);
    return;
  }
  v8::Local<v8::Value> val;
  args->GetNext(&val);
  if (val->IsNull()) {
    delegate->ContinueWithCertificate(nullptr, nullptr);
    return;
  }
  mate::Dictionary cert_data;
  if (!mate::ConvertFromV8(isolate, val, &cert_data)) {