### Preflight Checklist
* [x] I have read the [Contributing Guidelines](https://github.com/electron/electron/blob/master/CONTRIBUTING.md) for this project.
* [x] I agree to follow the [Code of Conduct](https://github.com/electron/electron/blob/master/CODE_OF_CONDUCT.md) that this project adheres to.
* [x] I have searched the issue tracker for an issue that matches the one I want to file, without success.

### Issue Details

* **Electron Version:**
  * 6.0.0-beta.3
* **Operating System:**
  * Windows 10 (1809)
* **Last Known Working Electron version:**:
  * 5.0.1

### Expected Behavior
Dragging your mouse to the bottom of the screen with a maximized frameless window and a hidden Windows taskbar should make the taskbar appear.

### Actual Behavior
The taskbar does not appear.

### To Reproduce

* Ensure you have Taskbar hiding enabled
![image](https://user-images.githubusercontent.com/144914/57793291-d12d9000-76f5-11e9-8c63-178e928a5358.png)

```sh
$ git clone https://github.com/adill/electron-quick-start -b no-taskbar-unhide
$ npm install
$ npm start || electron .
```

* Move your mouse to the bottom of the screen

### Screenshots

### Additional Information

atom/browser/native_window_views.cc
root_view_->SetAutoHideMenuBar(auto_hide);
}
bool NativeWindowViews::IsMenuBarAutoHide() {
  return root_view_->IsMenuBarAutoHide();
}
void NativeWindowViews::SetMenuBarVisibility(bool visible) {
  root_view_->SetMenuBarVisibility(visible);
}
bool NativeWindowViews::IsMenuBarVisible() {
  return root_view_->IsMenuBarVisible();
}
void NativeWindowViews::SetVisibleOnAllWorkspaces(bool visible,
                                                  bool visibleOnFullScreen) {
  widget()->SetVisibleOnAllWorkspaces(visible);
}
bool NativeWindowViews::IsVisibleOnAllWorkspaces() {
#if defined(USE_X11)
  
  
  XAtom sticky_atom = GetAtom("_NET_WM_STATE_STICKY");
  std::vector<XAtom> wm_states;
  ui::GetAtomArrayProperty(GetAcceleratedWidget(), "_NET_WM_STATE", &wm_states);
  return std::find(wm_states.begin(), wm_states.end(), sticky_atom) !=
         wm_states.end();
#endif
  return false;
}
gfx::AcceleratedWidget NativeWindowViews::GetAcceleratedWidget() const {