* Electron version: 1.4.4
* Operating system: win10

Hi,
Example described [here](https://github.com/electron/electron/blob/master/docs/api/global-shortcut.md) works with v1.4.0 but doesn't seem to work with v1.4.4 or v1.4.5.  Method `globalShortcut.isRegistered ` returns true, but the callback isn't called. 

Thanks!
atom/browser/api/atom_api_system_preferences.h
#ifndef ATOM_BROWSER_API_ATOM_API_SYSTEM_PREFERENCES_H_
#define ATOM_BROWSER_API_ATOM_API_SYSTEM_PREFERENCES_H_
#include <string>
#include "atom/browser/api/event_emitter.h"
#include "base/callback.h"
#include "base/values.h"
#include "native_mate/handle.h"
#if defined(OS_WIN)
#include "ui/gfx/sys_color_change_listener.h"
#endif
namespace base {
class DictionaryValue;