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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/native_window_views.cc
return;
  if (!menu_bar_) {
    gfx::Size content_size = GetContentSize();
    menu_bar_.reset(new MenuBar(this));
    menu_bar_->set_owned_by_client();
    if (!menu_bar_autohide_) {
      SetMenuBarVisibility(true);
      if (use_content_size_) {
        
        extensions::SizeConstraints constraints = GetContentSizeConstraints();
        if (constraints.HasMinimumSize()) {
          gfx::Size min_size = constraints.GetMinimumSize();
          min_size.set_height(min_size.height() + kMenuBarHeight);
          constraints.set_minimum_size(min_size);
        }
        if (constraints.HasMaximumSize()) {
          gfx::Size max_size = constraints.GetMaximumSize();
          max_size.set_height(max_size.height() + kMenuBarHeight);
          constraints.set_maximum_size(max_size);
        }
        SetContentSizeConstraints(constraints);
        
        SetContentSize(content_size);
      }
    }
  }
  menu_bar_->SetMenu(menu_model);
  Layout();
}
void NativeWindowViews::SetBrowserView(NativeBrowserView* view) {