Use Object.create(null) for maps.

This prevents inadvertent leakage of `Object` properties into the map.

Author: cscott

build.xml

@@ -113,7 +113,7 @@
             ${license.text}
             */
             /* Version v@VERSION@, Build time: ${RIGHT_NOW} */
-            var parserlib = {};
+            var parserlib = Object.create(null);
             (function(){
             </header>
             <!--<filelist dir="${src.dir}/util" files="EventTarget.js, StringReader.js, TokenStream.js"/> -->

src/css/TokenStream.js

@@ -40,7 +40,7 @@ function isIdentStart(c){
 
 function mix(receiver, supplier){
     for (var prop in supplier){
-        if (supplier.hasOwnProperty(prop)){
+        if (Object.prototype.hasOwnProperty.call(supplier, prop)){
             receiver[prop] = supplier[prop];
         }
     }

src/css/Tokens.js

@@ -180,7 +180,7 @@ var Tokens  = [
 (function(){
 
     var nameMap = [],
-        typeMap = {};
+        typeMap = Object.create(null);
 
     Tokens.UNKNOWN = -1;
     Tokens.unshift({name:"EOF"});

src/util/EventTarget.js

@@ -13,7 +13,7 @@ function EventTarget(){
      * @property _listeners
      * @private
      */
-    this._listeners = {};
+    this._listeners = Object.create(null);
 }
 
 EventTarget.prototype = {

src/util/TokenStreamBase.js

@@ -65,7 +65,7 @@ function TokenStreamBase(input, tokenData){
 TokenStreamBase.createTokenData = function(tokens){
 
     var nameMap     = [],
-        typeMap     = {},
+        typeMap     = Object.create(null),
         tokenData     = tokens.concat([]),
         i            = 0,
         len            = tokenData.length+1;