Bug 161401 [Viewers] Tweak ColumnViewer-API
- Rename getRowPart(Point point) => getViewerRow() - Rename getCell(Point point) => getViewerCell() - Rename setViewerColumn(final int columnIndex, ViewerColumn viewer) => setupEditingSupport - Make setupEditingSupport() private no one from external needs to use this API to set the EditingSupport for an ViewerColumn
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TableViewer.java
* @return ViewerRow
	 */
	private ViewerRow createNewRowPart(int style, int rowIndex) {
		TableItem item;
		if (rowIndex >= 0) {
			item = new TableItem(table, style, rowIndex);
		} else {
			item = new TableItem(table, style);
		}
		return getRowPartFromItem(item);
	}
	/**
	 * Returns the item at the given display-relative coordinates, or
	 * <code>null</code> if there is no item at that location.
	 * <p>
	 * The default implementation of this method returns <code>null</code>.
	 * </p>
	 * 
	 * @param x
	 *            horizontal coordinate
	 * @param y
	 *            vertical coordinate
	 * @return the item, or <code>null</code> if there is no item at the given
	 *         coordinates
	 */
	protected Item getItem(int x, int y) {
		return table.getItem(table.toControl(new Point(x, y)));
	}
}