改用这个，你不需要访问令牌或任何特殊的东西来获得他们的 个人资料图片，只是他们的 Facebook 用户 ID.

Use this instead, you don't need an access token or anything special to get their profile picture, just their facebook user id.

Accounts.onCreateUser(function(options, user) {
    if (options.profile) {
        options.profile.picture = "http://graph.facebook.com/" + user.services.facebook.id + "/picture/?type=large";
        user.profile = options.profile;
    }
    return user;
});