Problem with video playback in full screen mode in Windows Phone 8.1

I converted our WP 8.0 app to WP 8.1, the app has some videos, in Windows Phone 8.0, the videos are played on the built-in video player in full screen mode, but after converting the videos started to play inline in the listing on the screen itself. How do I play these videos with the built-in video player in full screen mode?

I am using HTML5 with JS for WP development.