Renders as markup the specified tree node value into the specified element, usually as a text node.
Default implementation delegates to the default {@link org.itsnat.core.domutil.ElementRenderer}.
Default implementation ignores isSelected, isExpanded, isLeaf and hasFocus (current implementation of ItsNat trees does not handle focus on tree nodes, ever is false).
@param tree the tree component, may be used to provide contextual information. Default implementation ignores it.
@param row the tree node row (seeing the tree as a list).
@param value the value to render.
@param isSelected true if the tree node is selected.
@param isExpanded true if the tree node is expanded.
@param isLeaf true if the tree node is a leaf.
@param hasFocus true if the tree node has the focus.
@param treeNodeLabelElem the tree node label element to render the value into. Is a hint, if provided should be obtained by calling
tree.getItsNatTreeUI().getLabelElementFromRow(row).
@param isNew true if this is the first time the markup is rendered. Default implementation ignores this parameter.