* [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.13
* **Operating System:** Windows 10

### Expected Behavior

When calling `browserWindow.setAlwaysOnTop(true)`, I expect the `always-on-top-changed` event to be called with the boolean `isAlwaysOnTop` parameter set to `true`, and vice versa.

### Actual Behavior

I experience the opposite of above: When calling `browserWindow.setAlwaysOnTop(true)`, my `always-on-top-changed` handler is called with `false`, and vice versa.

### To Reproduce

I don't have any JS code to share and I'm not a JS dev (I use F# and compile to JS with Fable). I think the issue should be easy to reproduce though.
shell/browser/native_window_views.cc
if (options.Get(options::kSkipTaskbar, &skip_taskbar) && skip_taskbar) {
    state_atom_list.push_back(GetAtom("_NET_WM_STATE_SKIP_TASKBAR"));
  }
  
  if (fullscreen) {
    state_atom_list.push_back(GetAtom("_NET_WM_STATE_FULLSCREEN"));
  }
  if (parent) {
    SetParentWindow(parent);
    
    window_type = "dialog";
    
    if (is_modal())
      state_atom_list.push_back(GetAtom("_NET_WM_STATE_MODAL"));
  }
  if (!state_atom_list.empty())
    ui::SetAtomArrayProperty(GetAcceleratedWidget(), "_NET_WM_STATE", "ATOM",
                             state_atom_list);
  
  if (!window_type.empty())
    SetWindowType(GetAcceleratedWidget(), window_type);
#endif
#if defined(OS_WIN)
  if (!has_frame()) {
    
    
    DWORD frame_style = WS_CAPTION | WS_OVERLAPPED;
    if (resizable_)
      frame_style |= WS_THICKFRAME;
    if (minimizable_)