* 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
#ifndef ATOM_BROWSER_NATIVE_WINDOW_MAC_H_
#define ATOM_BROWSER_NATIVE_WINDOW_MAC_H_
#import <Cocoa/Cocoa.h>
#include <string>
#include <vector>
#include "atom/browser/native_window.h"
#include "base/mac/scoped_nsobject.h"
#include "content/public/browser/render_widget_host.h"
@class AtomNSWindow;