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/PropertySearchStrategy.java
*/
	protected Object getPropertyFromSlotSelector( Module module,
			DesignElement element, ElementPropertyDefn prop )
	{
		if ( element.getContainer( ) == null )
			return null;
		String selector = element.getContainer( ).getSelector(
				element.getContainerSlot( ) );
		return getPropertyFromSelector( module, prop, selector );
	}
	/**
	 * Returns property value with predefined style.
	 * 
	 * @param module
	 *            module
	 * @param prop
	 *            definition of property to get
	 * @param selector
	 *            predefined style
	 * @return The property value, or null if no value is set.
	 */
	protected Object getPropertyFromSelector( Module module,
			ElementPropertyDefn prop, String selector )
	{
		assert module != null;
		if ( selector == null )
			return null;
		
		StyleElement style = module.findStyle( selector );
		if ( style != null )