Bug 164070 Support widows/orphans properties on text item
Support widows/orphans properties on block text item(label, text, data etc), About the definition of widows/orphans, please refer to CSS spec.
model/org.eclipse.birt.report.model.tests/test/org/eclipse/birt/report/model/api/DesignElementHandleTest.java
assertFalse( form.canContain( FreeForm.REPORT_ITEMS_SLOT,
				(DesignElementHandle) null ) );
		assertFalse( form.canContain( FreeForm.NO_SLOT,
				(DesignElementHandle) null ) );
		
		TableHandle table = factory.newTableItem( null, 1 );
		RowHandle row = (RowHandle) ( table.getHeader( ).get( 0 ) );
		
		assertTrue( row.canContain( TableRow.CONTENT_SLOT,
				ReportDesignConstants.CELL_ELEMENT ) );
		assertFalse( row.canContain( TableRow.NO_SLOT, factory.newCell( ) ) );
		
		row = factory.newTableRow( );
		CellHandle cell = factory.newCell( );
		cell.addElement( factory.newTableItem( null ), Cell.CONTENT_SLOT );
		row.addElement( cell, TableRow.CONTENT_SLOT );
		assertFalse( table.canContain( TableItem.HEADER_SLOT, row ) );
		
		row = (RowHandle) ( table.getHeader( ).get( 0 ) );
		cell = (CellHandle) ( row.getSlot( TableRow.CONTENT_SLOT ).get( 0 ) );
		assertFalse( cell.canContain( Cell.CONTENT_SLOT,
				ReportDesignConstants.TABLE_ITEM ) );
		assertFalse( cell.canContain( Cell.CONTENT_SLOT, factory
				.newTableItem( null ) ) );
		assertTrue( cell.canContain( Cell.CONTENT_SLOT, factory
				.newFreeForm( null ) ) );
		
		assertFalse( cell
				.canContain( Cell.CONTENT_SLOT, factory.newList( null ) ) );
		assertFalse( cell.canContain( Cell.CONTENT_SLOT,