Stunner - Bendpoints on SequenceFlows does not move when user moves entire diagram

When a selection is made surrounding an entire diagram and user move it, the bends from sequence flow seems stuck in main canvas and does not move.

There are two behaviors observed:
1) After moving the selection, user see directly that bends didn't move
2) Sometimes it is re-rendered correctly in canvas and the flow bends seem in correct position, but after saving the diagram and reopening it is a completely mess and the bends are not in the correct position

It seems related to RHPAM-1106, however the main canvas is the container and it is not needed subprocess or swilnes to reproduce the problem.

It is a critical issue as it may mess up complex diagrams and users will only notice it after reopening.

Update
After some analysis here are the root causes:

• On multiple selection, the bendpoints for selected connectors were not updated on the runtime model, only were upadted on the view (canvas) side. This causes that bendpoints are not on the right place on the Preview screen neither when saving/re-opening the diagram.
• If any operation was failing, for example adding a task into some invalid parent, everything is rollback to initial state but the connectors' bendpoints were not
• Was not possible to move the bendpoints for a given connector when grouping all them using the multiple selection area