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* 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
int i = GetAcceleratorIndex(key);
  if (i != -1)
    static_cast<SubmenuButton*>(child_at(i))->Activate(nullptr);
}
int MenuBar::GetItemCount() const {
  return menu_model_->GetItemCount();
}
bool MenuBar::GetMenuButtonFromScreenPoint(const gfx::Point& point,
                                           AtomMenuModel** menu_model,
                                           views::MenuButton** button) {
  gfx::Point location(point);
  views::View::ConvertPointFromScreen(this, &location);
  if (location.x() < 0 || location.x() >= width() || location.y() < 0 ||
      location.y() >= height())
    return false;
  for (int i = 0; i < child_count(); ++i) {
    views::View* view = child_at(i);
    if (view->GetMirroredBounds().Contains(location) &&
        (menu_model_->GetTypeAt(i) == AtomMenuModel::TYPE_SUBMENU)) {
      *menu_model = menu_model_->GetSubmenuModelAt(i);
      *button = static_cast<views::MenuButton*>(view);
      return true;
    }
  }
  return false;
}
const char* MenuBar::GetClassName() const {