Bug 149251 Inconsistent Handling of a Non-inheritable ROM Property
For a ROM property defined to be non-inheritable, an empty string property value should be consistently handled as an empty string, not as null. For example, an oda.dataSource extension defines a data source property with canInherit=false. When a oda-data-source handle get saved in a report design, it correctly includes the tag for such property, even when an empty string value is specified. <oda-data-source extensionID="my.oda.plugin" name="my Data Source" id="24"> ... <property name="ApplicationServer"></property> </oda-data-source> However, later when using the DE API to read its property value, a null is returned. Then when the report design is subsequently saved, the property tag is lost. Expects that an empty string value of a non-inhertiable property should be preserved.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
ISlotDefn slotDefn = getDefn( ).getSlot( slotId );
		assert slotDefn != null;
		if ( !slotDefn.canContain( defn ) )
			return false;
		
		
		
		String name = defn.getName( );
		if ( ReportDesignConstants.TEMPLATE_DATA_SET.equals( name )
				|| ReportDesignConstants.TEMPLATE_REPORT_ITEM.equals( name )
				|| ReportDesignConstants.TEMPLATE_ELEMENT.equals( name ) )
			return true;
		if ( getSlot( slotId ).getCount( ) > 0
				&& !slotDefn.isMultipleCardinality( ) )
			return false;
		return true;
	}
	/**
	 * Checks whether the element to insert can reside in the given module.
	 * 
	 * @param module
	 *            the root module of the element to add
	 * @param slotID
	 *            the slot ID to insert
	 * @param element
	 *            the element to insert
	 * @return false if the module is a library and the element to insert is a
	 *         template element or its content is a template element; or the
	 *         container is report design and slot is component slot and the
	 *         element to insert is a template element or its content is a