Property definitions

android $ NativeAssetFileDescriptor :: file_descriptor
	fun file_descriptor: NativeFileDescriptor in "Java" `{
		FileDescriptor fd =  self.getFileDescriptor();
		if (fd == null) {
			Log.e("AssetFileDesciptorError", "Can't retrieve the FileDescriptor of this AssetFileDescriptor");
		}
		return fd;
	`}
lib/android/assets_and_resources.nit:379,2--385,3