observe_constraints

Returns a `GListModel` to track the constraints that are part of the layout.

Calling this function will enable extra internal bookkeeping to track constraints and emit signals on the returned listmodel. It may slow down operations a lot.

Applications should try hard to avoid calling this function because of the slowdowns.

Parameters:

this	a `GtkConstraintLayout`

Returns:

a `GListModel` tracking the layout's constraints