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
addTemplateParam = new ContentRecord( module, module,
					ReportDesign.TEMPLATE_PARAMETER_DEFINITION_SLOT,
					templateParam, true );
		
		ContentReplaceRecord replaceRecord = new TemplateTransformRecord(
				module, element, slotID, oldElement, newElement );
		ActivityStack stack = getActivityStack( );
		stack.startFilterEventTrans( replaceRecord.getLabel( ) );
		try
		{
			
			removeContents( oldElement );
			
			dropUserProperties( oldElement );
			if ( oldElement.hasReferences( ) )
				adjustReferenceClients( (ReferenceableElement) oldElement,
						unresolveReference );
			adjustReferredClients( oldElement );
			adjustDerived( oldElement );
			
			if ( oldElement.getStyle( module ) != null )
			{
				StyleCommand styleCmd = new StyleCommand( module, oldElement );
				styleCmd.setStyle( null );
			}
			
			if ( oldElement.getExtendsElement( ) != null )
			{
				ExtendsCommand extendsCmd = new ExtendsCommand( module,
						oldElement );