MediaDevicesInfo interface contains information that describes a single media input or output device.
DOMString that is an identifier for the represented device that is persisted across sessions. It is un-guessable by other applications and unique to the origin of the calling application. It is reset when the user clears cookies (for Private Browsing, a different identifier is used that is not persisted across sessions).
DOMString that is a group identifier. Two devices have the same group identifier if they belong to the same physical device — for example a monitor with both a built-in camera and a microphone.
Returns an enumerated value that is either