Emit a signal whenever new MediaDevices are added to the DeviceEnumerator. This will allow CameraManager to be notified about the new devices and it can re-emumerate all the devices currently present on the system. Device enumeration by the CameraManger is an expensive operation hence, we want one signal emission per 'x' milliseconds to notify multiple devices additions as a single batch, by the DeviceEnumerator. Add a \todo to investigate the support for that. Signed-off-by: Umang Jain <email@uajain.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>