title: google api with javascript. get birthday and gender
body: <p>I think it must be simple but couldnt find an example.<br>
  I'm using the basic google signin example. with header tags (including birthday scope):  </p>
  
  <pre><code>&lt;meta name="google-signin-scope" content="profile email https://www.googleapis.com/auth/user.birthday.read" /&gt;
  &lt;meta name="google-signin-client_id" content="xxx my id xxx" /&gt;
  &lt;script src="https://apis.google.com/js/platform.js" async defer&gt;&lt;/script&gt;
  </code></pre>
  
  <p>and a defualt login button in the html body:</p>
  
  <pre><code>&lt;div id="gsignin" class="g-signin2" data-onsuccess="onSignIn" data-theme="dark"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>and js:</p>
  
  <pre><code>  function onSignIn(googleUser) {
          var profile = googleUser.getBasicProfile();
          console.log(googleUser);
          console.log("ID: " + profile.getId());
          console.log("Name: " + profile.getName());
          console.log("Image URL: " + profile.getImageUrl());
          console.log("Email: " + profile.getEmail());
          g_token = googleUser.getAuthResponse().id_token;
    }
  </code></pre>
  
  <p>All this works just fine, user is asked to grant permissions. and i get the general profile info. but i'm not sure how to obtain the birthday date, is it somehow in the returned object? do i need another call to the api?<br>
  I've seen lots of examples about using scopes but couldn't find <strong>how to actually read the data</strong>(birthday date)... same thing for gender, don't think there is a special scope for that, i guess it should be part of the basic profile info(?)<br>
  Thanks in advance</p>
  
  <p><strong>edit:</strong> just to clarify, i know i'm using the right scope. i don't know how to read the data. for example, after user authenticated - profile.getEmail() will return the email. what would return the birthday?</p>