Make sure the |options| param passed to passes is always an object

Pass code can be simpler as a result.

lib/compiler.js

@@ -22,6 +22,8 @@ module.exports = {
    * cause its malfunction.
    */
   compile: function(ast, options) {
+    if (options === undefined) { options = {}; }
+
     var that = this;
 
     utils.each(this.appliedPassNames, function(passName) {

lib/compiler/passes/generate-code.js

@@ -2,7 +2,7 @@ var utils = require("../../utils");
 
 /* Generates the parser code. */
 module.exports = function(ast, options) {
-  options = utils.clone(options) || {};
+  options = utils.clone(options);
   utils.defaults(options, {
     cache:              false,
     trackLineAndColumn: false,