Q:

Chrome identity api to get profile info

I want general profile information of user like birthdate, gender, username,etc. I am able to get email and unique profile id of user by using getProfileUserInfo method of identity api. 
It returns only email and id like this: 
userinfo Object {email: "hxxxxxxxxx@gmail.com", id: "1xxxxxxxxxxx49189xx"}

How do I get additional information?

A:

Although I am not sure about birthday, but you can get user's information like id, name, given_name, family_name, link, picture, gender , locale.
Code:
chrome.identity.getAuthToken({
    interactive: true
}, function(token) {
    if (chrome.runtime.lastError) {
        alert(chrome.runtime.lastError.message);
        return;
    }
    var x = new XMLHttpRequest();
    x.open('GET', 'https://www.googleapis.com/oauth2/v1/userinfo?alt=json&access_token=' + token);
    x.onload = function() {
        alert(x.response);
    };
    x.send();
});

Just make sure you add the url under scopes in manifest.json:
"oauth2": {
        "client_id": "XXXXX",
        "scopes": [
            "https://www.googleapis.com/auth/userinfo.email"
        ]   
    }  

