<!--
Thanks for opening an issue! A few things to keep in mind:

- The issue tracker is only for bugs and feature requests.
- Before reporting a bug, please try reproducing your issue against
  the latest version of Electron.
- If you need general advice, join our Slack: http://atom-slack.herokuapp.com
-->

* Electron version: 2.0.0-beta.3
* Operating system: Ubuntu 16.04.04 LTS

### Expected behavior

App menu should be visible

### Actual behavior

App menu is invisible

### How to reproduce

- Run `electron`
- Observe that the app menu is invisible. It is still possible to open submenus.

![screenshot from 2018-03-14 17-01-18](https://user-images.githubusercontent.com/19880051/37415303-7296c25e-27ab-11e8-8284-d213c8bf5230.png)

atom/browser/native_window_views.cc
if (event.GetType() == blink::WebInputEvent::kRawKeyDown &&
      !IsAltKey(event) && IsAltModifier(event)) {
    if (!menu_bar_visible_ &&
        (menu_bar_->GetAcceleratorIndex(event.windows_key_code) != -1))
      SetMenuBarVisibility(true);
    menu_bar_->ActivateAccelerator(event.windows_key_code);
    return;
  }
  if (!menu_bar_autohide_)
    return;
  
  if (event.GetType() == blink::WebInputEvent::kRawKeyDown && IsAltKey(event)) {
    
    menu_bar_alt_pressed_ = true;
  } else if (event.GetType() == blink::WebInputEvent::kKeyUp &&
             IsAltKey(event) && menu_bar_alt_pressed_) {
    
    menu_bar_alt_pressed_ = false;
    SetMenuBarVisibility(!menu_bar_visible_);
  } else {
    
    menu_bar_alt_pressed_ = false;
  }
}
void NativeWindowViews::ShowAutofillPopup(
    content::RenderFrameHost* frame_host,
    content::WebContents* web_contents,
    const gfx::RectF& bounds,
    const std::vector<base::string16>& values,