Bug 182000 Cross tab layout behavior
In the current approach of cross tab layout view, the arrow is associated with the first data item in the cell. - User cannot delete measure and level data items which have arrow with them. -Wenbin has concerns with the approach, as this will make the UI very restrictive. - Also user may want to delete data item and just show image in a cross tab cell. We had a discussion with Bang, and he has revised the mockups for the layout - The idea is that the arrow is associated with the cross tab cell and not data item. Let us know if there are any issues with supporting this.
xtab/org.eclipse.birt.report.item.crosstab.ui/src/org/eclipse/birt/report/item/crosstab/internal/ui/editors/editpolicies/VirtualCrosstabCellFlowLayoutEditPolicy.java
command.setLevelHandle( (LevelHandle)newObject );
				return command;
			}
			else if (newObject instanceof MeasureHandle && type == VirtualCrosstabCellAdapter.MEASURE_TYPE)
			{
				return new CreateMeasureViewCommand(adapter, (MeasureHandle)newObject);
			}
		}
		
		
		return super.getCreateCommand( request );
		
	}
	
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.designer.internal.ui.editors.schematic.editpolicies.ReportFlowLayoutEditPolicy#createAddCommand(org.eclipse.gef.EditPart,
	 *      org.eclipse.gef.EditPart, org.eclipse.gef.EditPart)
	 */
	protected Command createAddCommand( EditPart parent, EditPart child,
			EditPart after )
	{
		Object parentObj = parent.getModel( );
		
		Object afterObj = after == null ? null : after.getModel( );
		Object childParent = child.getParent( ).getModel( );
		if (parentObj instanceof VirtualCrosstabCellAdapter && childParent instanceof CrosstabCellAdapter)
		{
			CrosstabCellAdapter childAdapter = (CrosstabCellAdapter)childParent;