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/metadata/ElementDefn.java
* 
	 * @return the expression property definition list.
	 */
	public List getExpressions( )
	{
		return getPropertyListWithType( getProperties( ),
				PropertyType.EXPRESSION_TYPE );
	}
	/**
	 * Returns the expression property definition list of this element
	 * definition. Each one is the instance of <code>PropertyDefn</code>.
	 * 
	 * @return the expression property definition list.
	 */
	public List getLocalExpressions( )
	{
		return getPropertyListWithType( getLocalProperties( ),
				PropertyType.EXPRESSION_TYPE );
	}
	/**
	 * Returns the property definition list each of which is defined in given
	 * property definition list with the given type.
	 * 
	 * @param propList
	 *            the property definition to search
	 * @param type
	 *            property type code, It's the constant defined in
	 *            <code>PropertyType</code>.
	 * @return the property definition list
	 */