Bug 121498 When datasource/dataset deleted, the datasource/dataset property binding element haven't been deleted
When deleted the datasource/dataset, the datasource/dataset property binding element haven't been deleted. Expected result: This operation must be a transaction.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/ContentCommand.java
ContentException.DESIGN_EXCEPTION_WRONG_TYPE );
		if ( !slotInfo.isMultipleCardinality( ) && toSlot.getCount( ) > 0 )
			throw new ContentException( to, toSlotID,
					ContentException.DESIGN_EXCEPTION_SLOT_IS_FULL );
		if ( !to.canContain( module, toSlotID, content ) )
			throw new ContentException(
					to,
					toSlotID,
					content,
					ContentException.DESIGN_EXCEPTION_INVALID_CONTEXT_CONTAINMENT );
		ActivityStack stack = getActivityStack( );
		String label = ModelMessages
				.getMessage( MessageConstants.MOVE_ELEMENT_MESSAGE );
		stack.startTrans( label );
		ContentRecord record = new ContentRecord( module, element, fromSlotID,
				content, false );
		stack.execute( record );
		record = new ContentRecord( module, to, toSlotID, content, newPos );
		stack.execute( record );
		stack.commit( );
	}
	/**
	 * Moves an element from one slot to another at the specified position. The
	 * destination slot can be in the same element (unusual) or a different
	 * element (usual case). Use the other form of this method to move an
	 * element within the same slot.
	 * 
	 * @param content
	 *            The element to move.
	 * @param fromSlotID