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
* Creates the slot with the definition.
	 */
	protected final void initSlots( )
	{
		int slotCount = getDefn( ).getSlotCount( );
		if ( slotCount == 0 )
			return;
		slots = new ContainerSlot[slotCount];
		for ( int i = 0; i < slotCount; i++ )
		{
			SlotDefn slot = (SlotDefn) getDefn( ).getSlot( i );
			if ( slot.isMultipleCardinality( ) )
				slots[i] = new MultiElementSlot( );
			else
				slots[i] = new SingleElementSlot( );
		}
	}
	/**
	 * Returns the validation error list, each of which is the instance of
	 * <code>SemanticExcpetion</code>.
	 * 
	 * @return the validation error list.
	 */
	public List getErrors( )
	{
		if ( errors == null )
			return new ArrayList( );
		return errors;
	}
	/**