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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 opacity_;
}
void NativeWindowViews::SetIgnoreMouseEvents(bool ignore, bool forward) {
#if defined(OS_WIN)
  LONG ex_style = ::GetWindowLong(GetAcceleratedWidget(), GWL_EXSTYLE);
  if (ignore)
    ex_style |= (WS_EX_TRANSPARENT | WS_EX_LAYERED);
  else
    ex_style &= ~(WS_EX_TRANSPARENT | WS_EX_LAYERED);
  if (layered_)
    ex_style |= WS_EX_LAYERED;
  ::SetWindowLong(GetAcceleratedWidget(), GWL_EXSTYLE, ex_style);
  
  if (!ignore) {
    SetForwardMouseMessages(false);
  } else {
    SetForwardMouseMessages(forward);
  }
#elif defined(USE_X11)
  if (ignore) {
    XRectangle r = {0, 0, 1, 1};
    XShapeCombineRectangles(gfx::GetXDisplay(), GetAcceleratedWidget(),
                            ShapeInput, 0, 0, &r, 1, ShapeSet, YXBanded);
  } else {
    XShapeCombineMask(gfx::GetXDisplay(), GetAcceleratedWidget(),
                      ShapeInput, 0, 0, None, ShapeSet);
  }
#endif
}
void NativeWindowViews::SetContentProtection(bool enable) {