acceptDanger并打开不在chrome扩展中工作

Question

当我给它打开文件和acceptDanger函数都不起作用。对于打开文件，它提供所需的用户手势，并接受危险，不接受该文件。

我的background.js代码如下

 chrome.downloads.download({
  url: "http://meenkada.net84.net/tester.php",
  filename: "testfile.php" // Optional
},function(downloadId) {
   chrome.downloads.open(downloadId);
});


chrome.downloads.download({
  url: "http://meenkada.net84.net/test.bat",
  filename: "test.bat" // Optional
},function(downloadId) {
    chrome.downloads.acceptDanger(downloadId);
    alert('hi');
});

我的manifest.json如下

{
  "name": "__MSG_extName__",
  "version": "0.4",
  "description": "__MSG_extDescription__",
   "default_locale": "en",
   "page_action": {
    "default_icon": "icon16.png"
    },


    "background": {
    "scripts": [
       "background.js"
    ]
  },
  "permissions": [
    "proxy",
    "downloads",
    "downloads.shelf",
    "*://*.meenkada.net78.net/",
    "downloads.open"
  ],
   "incognito": "split",
  "manifest_version": 2
}