Android - Add function to remove unwanted elements from screen, e.g., settings buttons, and capture button.

[Mehequanna]

This function will be used to clear the screen of unwanted elements after the users taps the capture button.

Note: Currently I'm use the activity XML to handle things we don't want captured. So things that we want captured should be on the FaceArFragment.

[Mehequanna]

Closed because this is getting handled via other issues.