如何在chrome扩展上添加像tamparmonky这样的用户脚本

Question

您好我正在尝试创建Chrome扩展程序。它像tampermonky。它添加了一些用户脚本。但问题是某些变量显示未定义，但是当我在tampermonky上使用相同的脚本时，没有错误。 我的扩展名manifest.json是

{
    "name": "SayHello",
    "description": "It will say hello when a page finishied load.",
    "version": "0.4",
    "permissions": [
        "tabs",
        "<all_urls>",
        "storage"
    ],
    "browser_action": {
        "default_icon": "icon.png"
    },
    "options_page": "options.html",
    "content_scripts": [
        {
            "exclude_globs":[],
            "include_globs":["*"],
            "matches": [
                "http://www.amazon.com/*",
                "https://www.amazon.com/*"
            ],
            "js": ["email.js"],
            "run_at": "document_end"
        }
    ], 
    "converted_from_user_script": true,
    "manifest_version":2
}

和email.js是。

P.when("jQuery","ready").execute(function(t){
    var i="http://www.amazon.com/gp/profile/A3U7NCDBQ95EJM/customer_email";
    t.get(i,function(t){
        var o=t.data.email;
        console.log('o:'+o);
    });
    return t;
});

错误按摩是Uncaught ReferenceError: P is not defined