'FB' is not defined in HounCI Test

I am using the following code to share an article via facebook.

$.getScript('//connect.facebook.net/en_US/sdk.js', function() {
        FB.init({
            appId: '505159549666382',
            version: 'v2.5'
        });
        FB.ui({
            method: 'share',
            display: 'popup',
            href: audio,
            caption: name,
            description: desc,
            picture: img
        });
    });

I am however encountering an issue that that FB Object is not defined when I make a pull request which is inspected by a js inspector.

Can someone explain how and at what point the FB Object is declared?

Thanks,.