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
* Returns the optional display name. Note: set the display name by calling
	 * the {@link #setProperty( String, Object )}method.
	 * <p>
	 * Part of: The name system.
	 * 
	 * @return Returns the displayName.
	 */
	public String getDisplayName( )
	{
		return (String) getLocalProperty( null, DISPLAY_NAME_PROP );
	}
	/**
	 * Returns the optional message id used to localize the display name. Note:
	 * set the display name id by calling the
	 * {@link #setProperty( String, Object )}method.
	 * <p>
	 * Part of: The name system.
	 * 
	 * @return Returns the displayNameID.
	 */
	public String getDisplayNameID( )
	{
		return (String) getLocalProperty( null, DISPLAY_NAME_ID_PROP );
	}
	/**
	 * Sets the unique ID for this element. The ID can be set only once, when
	 * the element is first added to the design.
	 * 
	 * @param newID
	 *            The id to set.