In order to support the extended network model going forwards, the method Opm::Group::parent() is split in the API into two new methods, Opm::Group::control_group() and Opm::Group::flow_group(). These methods give the names of the parent node in the group control hierarchy and network structure, respectively.
While for the standard network model these two values will be the same (and the same as ::parent()), code that presently calls ::parent() should be revisited with an eye to the question of which parent group is desired.
13e838d171