Bug 124620 Referenced Parameter icon should be invalid if the parameter in library is deleted
Description: Referenced parameter icon should be invalid if the source parameter in library is deleted. Steps to reproduce: 1.Create a library. Insert a report scalar parameter. 2.Create a report, use the above library. In the library explorer, pull the parameter to the data explorer view of report. 3.Open the library file, delete the parameter. Then reopen the report design file, the icon of parameter seems nothing happened. But if those operations happened in dataset, the icon of dataset in the report will be invalid. It is acceptable. Expected Result: The icon of referenced parameter should be invalid.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
* @param propName
	 *            The name of the property to validate.
	 * @param value
	 *            The value to validate
	 * @return The validated value.
	 * @throws PropertyNameException
	 *             If the property is undefined.
	 * @throws PropertyValueException
	 *             If the value is incorrect.
	 */
	public Object validatePropertyValue( Module module, String propName,
			Object value ) throws PropertyNameException, PropertyValueException
	{
		
		
		ElementPropertyDefn prop = getPropertyDefn( propName );
		if ( prop == null )
			throw new PropertyNameException( this, propName );
		
		try
		{
			return prop.validateValue( module, value );
		}
		catch ( PropertyValueException e )
		{
			
			e.setElement( this );
			e.setPropertyName( propName );
			throw e;
		}