Updates the state of the given user activity.
- macOS 10.10+
The user activity to be updated.
Subclasses override this method to update the state of the supplied
user. Add state representing the user's activity into
user using its
add method. When the state is dirty, set the
needs property to
NSUser object managed by AppKit is updated, an empty
user dictionary is given to the user activity, and all of the objects associated with the user activity are sent an