get asset info including location from uiimage

uiimageasset.cs

				var refurl = obj.ValueForKey(UIImagePickerController.ReferenceUrl) as NSUrl;

				//TODO: refurl is null on newly taken images
				var lib = new ALAssetsLibrary();
				lib.AssetForUrl(refurl, (ALAsset asset) => {
					var loc = asset.Location;

				}, (NSError error) => {
					
				});