Bug 315281 update copyrights for 3.6
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
/*
	 * (non-Javadoc) Method declared in AbstractTreeViewer.
	 */
	protected void addTreeListener(Control c, TreeListener listener) {
		((Tree) c).addTreeListener(listener);
	}
	/*
	 * (non-Javadoc)
	 *
	 * @see org.eclipse.jface.viewers.ColumnViewer#getColumnViewerOwner(int)
	 */
	protected Widget getColumnViewerOwner(int columnIndex) {
		if (columnIndex < 0 || ( columnIndex > 0 && columnIndex >= getTree().getColumnCount() ) ) {
			return null;
		}
		if (getTree().getColumnCount() == 0)
			return getTree();
		return getTree().getColumn(columnIndex);
	}
	/*
	 * (non-Javadoc) Method declared in AbstractTreeViewer.
	 */
	protected Item[] getChildren(Widget o) {
		if (o instanceof TreeItem) {
			return ((TreeItem) o).getItems();
		}
		if (o instanceof Tree) {
			return ((Tree) o).getItems();
		}
		return null;