Bug 174701 [Viewers] ViewerRow should be reused instead of connected to the Item
Currently we create a ViewerRow ver every Item we create this can degrade performance, we should cache the row and reuse it
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ColumnViewer.java
* @param columnOwner
	 *            the column widget
	 * @param labelProvider
	 *            the label provider to use for the column
	 * @return ViewerColumn the viewer column
	 */
	private ViewerColumn createViewerColumn(Widget columnOwner,
			CellLabelProvider labelProvider) {
		ViewerColumn column = new ViewerColumn(this, columnOwner) {
		};
		column.setLabelProvider(labelProvider, false);
		return column;
	}
	/**
	 * Update the cached cell object with the given row and column.
	 * 
	 * @param rowItem
	 * @param column
	 * @return ViewerCell
	 */
	ViewerCell updateCell(ViewerRow rowItem, int column) {
		cell.update(rowItem, column);
		return cell;
	}
	/**
	 * Returns the {@link Item} at the given widget-relative coordinates, or
	 * <code>null</code> if there is no item at the given coordinates.
	 * 
	 * @param point
	 *            the widget-relative coordinates