Bug 119550 Default Value of Named Expression can't be saved in design file
New a report, set named expression in the report property editor add a named expression and set the default value add a report item, say table, to the layout set the named expression of the report item add a named expression and set hte default value save the report close the report and reopen, and there is no default named expression value displayed. open report design file with a text editor, there is no default value associate with the named expression
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/core/UserPropertyDefn.java
assert false;
		}
		return null;
	}
	/**
	 * Gets the definition of the structure which represents the user property
	 * definition.
	 * 
	 * @return structure definition.
	 */
	public IStructureDefn getDefn( )
	{
		return MetaDataDictionary.getInstance( ).getStructure( STRUCTURE_NAME );
	}
	/**
	 * Gets the object definition of the user property definition.
	 * 
	 * @return object definition.
	 * 
	 */
	public IObjectDefn getObjectDefn( )
	{
		return MetaDataDictionary.getInstance( ).getStructure( STRUCTURE_NAME );
	}
	/**
	 * Gets the display name of this user property definition. The search will
	 * check the translation dictionary firstly, then look at the instance
	 * itself. If no display name defined, the XML name will be returned.
	 * 
	 * @return display name of this user property.