How to use the emmet/emmet.resetUserData function in emmet

dir.exists(function(err, exists) {
				if (exists) {
					emmet.resetUserData();
					dir.getContents(function(err, files) {
						if (err) {
							return callback(err);
						}

						files = files.filter(function(entry) {
							return !entry.isDirectory;
						});

						var complete = function() {
							emmet.loadExtensions(files);
							callback();
						};

						var waitForKeymap = false;