性能提升：Object.freeze 是不必要的，因为每个 listener 得到的对象都是一个新对象，改动了也不会影响其他 listener

package.json

@@ -1,6 +1,6 @@
 {
   "name" : "chrome-storage-wrapper" ,
-  "version" : "0.1.1" ,
+  "version" : "0.1.2" ,
   "description" : "A tiny wrapper for chrome.storage that using Promise." ,
   "author" : {
     "name" : "Milk Lee" ,

release/chrome-storage.js

@@ -177,8 +177,8 @@
          * 删除一个监听函数
          * @param {Function} listener
          */
-        removeChangeListener: function removeChangeListener(listener) {
-            var index = changeCallbacks.indexOf(listener);
+        removeChangeListener: function removeChangeListener(newListener) {
+            var index = changeCallbacks.indexOf(newListener);
             if (index >= 0) {
                 changeCallbacks.splice(index, 1);
             }
@@ -214,9 +214,8 @@
             customChanges[key] = changes[key].newValue;
         }
 
-        // 防止对象在回调里被修改，因为这会导致其它回调也收到修改后的对象
-        changeCallbacks.forEach(function (listener) {
-            listener(Object.freeze(customChanges), area);
+        changeCallbacks.forEach(function (newListener) {
+            newListener(customChanges, area);
         });
     });
 

src/chrome-storage.es6

@@ -187,8 +187,8 @@
          * 删除一个监听函数
          * @param {Function} listener
          */
-            removeChangeListener ( listener ) {
-            const index = changeCallbacks.indexOf( listener );
+            removeChangeListener ( newListener ) {
+            const index = changeCallbacks.indexOf( newListener );
             if ( index >= 0 ) {
                 changeCallbacks.splice( index , 1 );
             }
@@ -202,9 +202,8 @@
             customChanges[ key ] = changes[ key ].newValue;
         }
 
-        // 防止对象在回调里被修改，因为这会导致其它回调也收到修改后的对象
-        changeCallbacks.forEach( ( listener ) => {
-            listener( Object.freeze( customChanges ) , area );
+        changeCallbacks.forEach( ( newListener ) => {
+            newListener( customChanges , area );
         } );
     } );