<!--
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/ui/views/menu_bar.cc
UpdateMenuBarColor();
}
void MenuBar::UpdateMenuBarColor() {
#if defined(OS_WIN)
  background_color_ = color_utils::GetSysSkColor(COLOR_MENUBAR);
#elif defined(USE_X11)
  GetMenuBarColor(&enabled_color_, &disabled_color_, &highlight_color_,
                  &hover_color_, &background_color_);
#endif
  SetBackground(views::CreateSolidBackground(background_color_));
}
}