Bug 210716 Support switch Text/Chart view in crosstab cell
Need crosstab UI provide support to switch between Text and Chart view in measure/aggregation cell.
xtab/org.eclipse.birt.report.item.crosstab.core/src/org/eclipse/birt/report/item/crosstab/core/de/internal/CrosstabModelUtil.java
* 
	 * @param crosstab
	 * @param axisType
	 * @return
	 */
	public static int getAllLevelCount( CrosstabReportItemHandle crosstab,
			int axisType )
	{
		if ( crosstab == null )
			return 0;
		int count = 0;
		for ( int i = 0; i < crosstab.getDimensionCount( axisType ); i++ )
		{
			DimensionViewHandle dimensionView = crosstab.getDimension( axisType,
					i );
			count += dimensionView.getLevelCount( );
		}
		return count;
	}
	/**
	 * Gets the preceding level in the crosstab.
	 * 
	 * @param levelView
	 *            the level view to search the preceding one
	 * @return the preceding leve for the given if found, otherwise null
	 */
	public static LevelViewHandle getPrecedingLevel( LevelViewHandle levelView )
	{
		if ( levelView == null )
			return null;