[2957] Fix custom node child previous position on layout

Bug: #2957
Signed-off-by: Florian ROUËNÉ <florian.rouene@obeosoft.com>

CHANGELOG.adoc

@@ -112,6 +112,7 @@ Now, for a multi-valued feature, the values are properly displayed and the delet
 - https://github.com/eclipse-sirius/sirius-web/issues/2912[#2912] [diagram] Send all requested node descriptions to the frontend when requested.
 - https://github.com/eclipse-sirius/sirius-web/issues/2678[#2678] [diagram] Fix an issue where tools from the diagram palette where not executed.
 - https://github.com/eclipse-sirius/sirius-web/issues/2943[#2943] [view] Fix an issue where the default colors were not applied to sub-nodes and border nodes.
+- https://github.com/eclipse-sirius/sirius-web/issues/2957[#2957] [diagram] Fix an issue where childs of custom node lose their position.
 
 === New Features
 

packages/sirius-web/frontend/sirius-web/src/nodes/EllipseNodeLayoutHandler.ts

@@ -61,7 +61,7 @@ export class EllipseNodeLayoutHandler implements INodeLayoutHandler<NodeData> {
     // Update children position to be under the label and at the right padding.
     directNodesChildren.forEach((child, index) => {
       const previousNode = (previousDiagram?.nodes ?? []).find((previouseNode) => previouseNode.id === child.id);
-      const previousPosition = computePreviousPosition(previousNode, node);
+      const previousPosition = computePreviousPosition(previousNode, child);
       const createdNode = newlyAddedNode?.id === child.id ? newlyAddedNode : undefined;
 
       if (!!createdNode) {