Returns the associated device to device, if device is of type
GDK_DEVICE_TYPE_MASTER, it will return the paired pointer or
keyboard.
If device is of type GDK_DEVICE_TYPE_SLAVE, it will return
the master device to which device is attached to.
If device is of type GDK_DEVICE_TYPE_FLOATING, NULL will be
returned, as there is no associated device.
Returns the associated device to device, if device is of type GDK_DEVICE_TYPE_MASTER, it will return the paired pointer or keyboard. If device is of type GDK_DEVICE_TYPE_SLAVE, it will return the master device to which device is attached to. If device is of type GDK_DEVICE_TYPE_FLOATING, NULL will be returned, as there is no associated device.