- Electron version: 1.2.2
- Operating system: OS X 10.11.5

Add a listener for [`NSUserDefaultsDidChangeNotification`](https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSUserDefaults_Class/#//apple_ref/c/data/NSUserDefaultsDidChangeNotification):

```
systemPreferences.subscribeNotification('NSUserDefaultsDidChangeNotification', () => {
  // never gets here :(
});
```

Pop open System Preferences and change something under text (spelling, substitutions, or smart quotes). The notification never arrives. Have I misunderstood this API? Example usage [here](https://github.com/CharlieHess/electron-text-substitutions/blob/master/src/index.js#L46).

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 "native_mate/handle.h"
namespace base {
class DictionaryValue;
}
namespace atom {
namespace api {
class SystemPreferences : public mate::EventEmitter<SystemPreferences> {