delete(filename) {
		return new Promise((resolve, reject) => {
			reject = setMessage(reject);
			window.resolveLocalFileSystemURL(
				filename,
				(entry) => {
					if (entry.isFile) {
						entry.remove(resolve, reject);
					} else {
						entry.removeRecursively(resolve, reject);
					}
				},
				reject,
			);
		});
	}
Delete a file or directory
@param {string} filename
@returns {Promise}