Bug 211703 Support muti-view on report item.
As title described.
xtab/org.eclipse.birt.report.item.crosstab.core/src/org/eclipse/birt/report/item/crosstab/core/de/internal/CrosstabReportItemTask.java
*            the position index of the dimension to remove, 0-based integer
	 * @throws SemanticException
	 */
	public void removeDimension( int axisType, int index )
			throws SemanticException
	{
		CrosstabViewHandle crosstabView = crosstab.getCrosstabView( axisType );
		if ( crosstabView != null )
		{
			crosstabView.removeDimension( index );
		}
	}
	private MultiViewsHandle getMultiViews( )
	{
		return (MultiViewsHandle) crosstab.getModelHandle( ).getProperty(
				MULTI_VIEWS_PROP );
	}
	/**
	 * Returns the view that is being used.
	 * 
	 * @return the view that is being used
	 */
	public DesignElementHandle getCurrentView( )
	{
		MultiViewsHandle multiView = getMultiViews( );
		if ( multiView == null
				|| multiView.getIntProperty( MultiViewsHandle.INDEX_PROP ) == MultiViewsHandle.HOST )
			return crosstab.getModelHandle( );
		return multiView.getCurrentView( );
	}