XX for List/Tree/TreeTableRow

Happens if the cell is not yet attached to a List/Tree/TableView (there might be others, didn't really dig), see failing tests below. In real-world scenarios, this might happen if custom skins are set in a cellFactory.

incorrect assumption ;-) The part in square brackets happens a couple of lines later ...
[
The technical reason is that skin registeres a changeListener to a property of the containing view, that is something like

registerChangeListener(cell.getXXView().getSomeProperty(), ....)

Technical solution is to move the binding into the listener to the cell.XXView property
]

Constructor is directly accessing the indirect property:

for list/tree

this.fixedCellSize = control.getTreeView().getFixedCellSize();

for treeTableRow, it's buried a bit deeper ... getVisibleColumns assumes that the cell is attached to a containing view

Failing tests:

    /**
     * Test about treeTableRowSkin: registers
     * a listener on the treeTableView treeColumn in constructor
     * - throws if not yet bound to a treeTable
     */
    @Test
    public void testTreeTableRowSkinInit() {
        TreeTableRow row = new TreeTableRow();
        row.setSkin(new TreeTableRowSkin(row));
    }
    
    @Test
    public void testListCellSkinInit() {
        ListCell cell = new ListCell();
        cell.setSkin(new ListCellSkin(cell));
    }
    
    @Test
    public void testTreeCellSkin() {
        TreeCell cell = new TreeCell();
        cell.setSkin(new TreeCellSkin(cell));
    }