Chrome has the public intent to deprecate powerful features like geolocation on non-secure origins, and they hope that other browsers will follow. Starting with Chrome 50, Chrome no longer supports obtaining the user's location using the HTML5 Geolocation API from pages delivered by non-secure connections. This means that the page that's making the Geolocation API call must be served from a secure context such as HTTPS. It is an important issue as it will directly impact any site that requires the use of the geolocation API and is not served over HTTPS. Here is the announcement.

So from now, your site must have HTTPS Secure URL if you want to use Google Chrome GeoLocation API. Firefox hasn’t implemented this feature yet so GeoLocation Prompt will appear in Firefox.