* Electron version: 1.4.12
* Operating system: OSX 10.11

If a BrowserWindow is created in full screen mode (fullScreen: true), but programmatically enters and exits kiosk mode (setKiosk(false)), I would expect the app to stay fullScreen at all times.  

This issue appears to be in **NativeWindowMac::SetKiosk(bool kiosk)**. It calls SetFullScreen(true) when entering kiosk and SetFullScreen(false) when leaving kiosk. It would be nice if a check was made to see if the window was already full screen and then just skip these calls. This would allow more graceful kiosking for full screen apps.  


atom/browser/native_window_mac.h
gfx::Rect WindowBoundsToContentBounds(const gfx::Rect& bounds);
  void UpdateDraggableRegions(
      const std::vector<DraggableRegion>& regions) override;
  void ShowWindowButton(NSWindowButton button);
  void InstallView();
  void UninstallView();
  
  
  void UpdateDraggableRegionViews(const std::vector<DraggableRegion>& regions);
  void RegisterInputEventObserver(content::RenderViewHost* host);
  void UnregisterInputEventObserver(content::RenderViewHost* host);
  base::scoped_nsobject<AtomNSWindow> window_;
  base::scoped_nsobject<AtomNSWindowDelegate> window_delegate_;
  
  id wheel_event_monitor_;
  
  base::scoped_nsobject<FullSizeContentView> content_view_;
  std::vector<DraggableRegion> draggable_regions_;
  bool is_kiosk_;
  bool zoom_to_page_width_;
  NSInteger attention_request_id_;  
  
  NSApplicationPresentationOptions kiosk_options_;
  
  TitleBarStyle title_bar_style_;
  DISALLOW_COPY_AND_ASSIGN(NativeWindowMac);
};
}  
#endif