How to get the file path to a CameraRoll loaded image?

Question

I would like to get the file path of an image that got loaded over the CameraRoll with the code below. The app runs on an iPhone with iOS 8 an it's build with Adobe Air 15.

var loaderCameraRoll:Loader 
var deviceCameraRoll:CameraRoll

function loadImageFromCameraRoll(e:Event=null):void {
deviceCameraRoll = new CameraRoll();
deviceCameraRoll.addEventListener(MediaEvent.SELECT, onSelectCameraRoll);
deviceCameraRoll.browseForImage();
}

function onSelectCameraRoll(event:MediaEvent):void {
var promise:MediaPromise = event.data as MediaPromise;
loaderCameraRoll = new Loader() 
loaderCameraRoll.contentLoaderInfo.addEventListener(Event.COMPLETE, onLoadedCameraRoll);
loaderCameraRoll.loadFilePromise(promise);      
}

function onLoadedCameraRoll(event:Event):void {
trace("Loaded - File path: ?")
}