Fix lint error.

Author: Oden

lib/loader.js

@@ -19,7 +19,8 @@ module.exports = function(content, map) {
 	var sourceMap = query.sourceMap || false;
 	var resolve = createResolver(query.alias);
 	// Inherit getLocalIdent from parent loader
-	if(this._module.issuer && this._module.issuer.loaders) {
+	/* eslint-disable no-underscore-dangle */
+	if(this._module && this._module.issuer && this._module.issuer.loaders) {
 		var filename = require.resolve("..");
 		var parentLoader = this._module.issuer.loaders.filter(function(loader) {
 			return loader.loader === filename;
@@ -29,6 +30,8 @@ module.exports = function(content, map) {
 		}
 	}
 
+	/* eslint-ensable no-underscore-dangle */
+
 	if(sourceMap) {
 		if (map) {
 			if (typeof map === "string") {