RFR: 8356770: TreeTableView not updated after removing a TreeItem with children and adding it to another parent

[Andy Goryachev]

On Wed, 12 Nov 2025 14:21:22 GMT, Ziad El Midaoui <zelmidaoui at openjdk.org> wrote:

> When a subtree is moved in a `TreeTableView` , the visuals don’t update until a resize or expand/collapse. The `TreeTableViewSkin` only rebuilds cells when the expanded row count changes.
> This PR makes the skin to detect structural changes on `childrenModificationEvent` using new variable `treeStructureDirty`, and in `updateItemCount()` call `requestRebuildCells()` to refresh the visuals.

I see no ill effects with the reproducer and the monkey tester (which was updated to add data manipulation context menus, see https://github.com/andy-goryachev-oracle/MonkeyTest ).

I suppose adding a flag in the skin (as opposed to similar flag in `VirtualContainerBase`) is ok since it deals with tree-table-specific functionality.

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Marked as reviewed by angorya (Reviewer).

PR Review: https://git.openjdk.org/jfx/pull/1971#pullrequestreview-3456069283