* Electron version: 1.4.14
* Operating system: Windows 8.1

### Expected behavior

A fullscreen transparent window should be transparent.

### Actual behavior

The window is not transparent (has a white background).

### How to reproduce

```
electron.app.on("ready", function () {
    var win = new BrowserWindow({
        show: true,
        frame: false,
        fullscreen: true,
        transparent: true
    });
});
```

Refs https://github.com/electron/electron/issues/8321#issuecomment-273615701


atom/browser/native_window_views.cc
SetFullScreen(kiosk);
}
bool NativeWindowViews::IsKiosk() {
  return IsFullscreen();
}
void NativeWindowViews::SetBackgroundColor(const std::string& color_name) {
  
  SkColor background_color = ParseHexColor(color_name);
  set_background(views::Background::CreateSolidBackground(background_color));
#if defined(OS_WIN)
  
  HBRUSH brush = CreateSolidBrush(skia::SkColorToCOLORREF(background_color));
  ULONG_PTR previous_brush = SetClassLongPtr(
      GetAcceleratedWidget(),
      GCLP_HBRBACKGROUND,
      reinterpret_cast<LONG_PTR>(brush));
  if (previous_brush)
    DeleteObject((HBRUSH)previous_brush);
#endif
}
void NativeWindowViews::SetHasShadow(bool has_shadow) {