Bug 159918 [Viewers] TreeViewer.setChildCount(...) should preserve selection
Since changing the child count of an element in a tree can effectively remove children, the #setChildCount(...) method should preserve selection. This way if a selected item is disposed, the selection change will fire with the new <empty selection>.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
}
	/**
	 * Starts editing the given element.
	 * 
	 * @param element
	 *            the element
	 * @param column
	 *            the column number
	 * @since 3.1
	 */
	public void editElement(Object element, int column) {
		treeViewerImpl.editElement(element, column);
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.viewers.ColumnViewer#getCellEditors()
	 */
	public CellEditor[] getCellEditors() {
		return treeViewerImpl.getCellEditors();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.viewers.ColumnViewer#getCellModifier()
	 */
	public ICellModifier getCellModifier() {
		return treeViewerImpl.getCellModifier();
	}
	/*