Bug 315281 update copyrights for 3.6
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ViewerColumn.java
* implementation.
	 * <p>
	 * Users setting up an editable {@link TreeViewer} or {@link TableViewer} with more than 1 column <b>have</b>
	 * to pass the SWT.FULL_SELECTION style bit when creating the viewer
	 * </p>
	 * @param editingSupport
	 *            The {@link EditingSupport} to set.
	 */
	public void setEditingSupport(EditingSupport editingSupport) {
		this.editingSupport = editingSupport;
	}
	/**
	 * Refresh the cell for the given columnIndex. <strong>NOTE:</strong>the
	 * {@link ViewerCell} provided to this method is no longer valid after this
	 * method returns. Do not cache the cell for future use.
	 * 
	 * @param cell
	 *            {@link ViewerCell}
	 */
	void refresh(ViewerCell cell) {
		CellLabelProvider labelProvider = getLabelProvider();
		if (labelProvider == null) {
			Assert.isTrue(false, "Column " + cell.getColumnIndex() + 
			" has no label provider."); 
		}
		labelProvider.update(cell);
	}
	/**
	 * Disposes of the label provider (if set), unregisters the listener and
	 * nulls the references to the label provider and editing support. This