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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
if (is_modal() && NativeWindow::parent()) {
    NativeWindowViews* parent =
        static_cast<NativeWindowViews*>(NativeWindow::parent());
    
    parent->SetEnabled(true);
    
    parent->Focus(true);
  }
  NotifyWindowClosed();
}
views::View* NativeWindowViews::GetInitiallyFocusedView() {
  return focused_view_;
}
bool NativeWindowViews::CanResize() const {
  return resizable_;
}
bool NativeWindowViews::CanMaximize() const {
  return resizable_ && maximizable_;
}
bool NativeWindowViews::CanMinimize() const {
#if defined(OS_WIN)
  return minimizable_;
#elif defined(USE_X11)
  return true;
#endif
}
base::string16 NativeWindowViews::GetWindowTitle() const {
  return base::UTF8ToUTF16(title_);
}
bool NativeWindowViews::ShouldHandleSystemCommands() const {