* 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
#if defined(OS_WIN)
  if (has_frame())
    FlipWindowStyle(GetAcceleratedWidget(), resizable, WS_THICKFRAME);
#elif defined(USE_X11)
  if (resizable != resizable_) {
    
    
    if (resizable) {
      SetContentSizeConstraints(old_size_constraints_);
    } else {
      old_size_constraints_ = GetContentSizeConstraints();
      resizable_ = false;
      gfx::Size content_size = GetContentSize();
      SetContentSizeConstraints(
          extensions::SizeConstraints(content_size, content_size));
    }
  }
#endif
  resizable_ = resizable;
}
bool NativeWindowViews::IsResizable() {