Parses a device-changed message. The device-changed message is produced by
#GstDeviceProvider or a #GstDeviceMonitor. It announces the
disappearance of monitored devices. * It announce that a device properties has
changed and @device represents the new modified version of @changed_device.
Parses a device-changed message. The device-changed message is produced by #GstDeviceProvider or a #GstDeviceMonitor. It announces the disappearance of monitored devices. * It announce that a device properties has changed and @device represents the new modified version of @changed_device.