[TreeTableView] graphic property of TreeItem is not displayed properly

If the treeItems of the treeTable have a graphic property, then the graphic property is displayed over the disclosure arrow button. The right border of the cell containing the graphic is also 'pushed' to the right, and looses its vertical alignment with the cells above and below it.

The problem comes from TreeTableRowSkin layoutChildren method:
-First: The method is not taking care of laying out the graphic property. (you can see in the code that getGraphic() is only used to compute the padding, but nowhere else). This is causing the graphic property to display on top of the disclosure arrow.
- Second: when computing the size of the cells, the getGraphic() size and padding are not being used for computing the resize / relocate value. This is causing the cells borders to look "pushed" further to the right.