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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/submenu_button.cc
views::MenuButton::PaintButtonContents(canvas);
  if (show_underline_ && (underline_start_ != underline_end_)) {
    int padding = (width() - text_width_) / 2;
    int underline_height = (height() + text_height_) / 2 - 2;
    canvas->DrawLine(gfx::Point(underline_start_ + padding, underline_height),
                     gfx::Point(underline_end_ + padding, underline_height),
                     underline_color_);
  }
}
bool SubmenuButton::GetUnderlinePosition(const base::string16& text,
                                         base::char16* accelerator,
                                         int* start, int* end) {
  int pos, span;
  base::string16 trimmed = gfx::RemoveAcceleratorChar(text, '&', &pos, &span);
  if (pos > -1 && span != 0) {
    *accelerator = base::ToUpperASCII(trimmed[pos]);
    GetCharacterPosition(trimmed, pos, start);
    GetCharacterPosition(trimmed, pos + span, end);
    return true;
  }
  return false;
}
void SubmenuButton::GetCharacterPosition(
    const base::string16& text, int index, int* pos) {
  int height = 0;
  gfx::Canvas::SizeStringInt(text.substr(0, index), gfx::FontList(), pos,
                             &height, 0, 0);
}
}