Nyall Dawson 81b934d9d1 Rework API and improve memory handling of graph objects
Instead of QgsGraphBuilder::graph() taking the ownership of the graph
and leaving the QgsGraphBuilder in an unpredictable state, add an
explicit "takeGraph" method which takes the existing graph and
make the existing "graph" method just return a copy of the graph.

Also fix corresponding memory leaks in network analysis processing
algorithms.

Fixes #44079
2021-07-20 13:54:46 +10:00
..
2021-07-07 13:46:11 +07:00