`IndexOutOfBoundsException` when wrapping at node with layer constraint

[protogenes]

LongEdgeJoiner tries to get the in/outgoing edge, which is not attached to the port. I guess it was removed by LayerConstraintPreprocessor.

algorithm: layered
wrapping.strategy: SINGLE_EDGE
wrapping.correctionFactor: 0.0001 // force cut

node n1
node n2
node n3
node n4
node n5 {
    layering.layerConstraint: LAST_SEPARATE
}

edge n1->n2
edge n2->n3
edge n3->n4
edge n4->n2
edge n3->n5