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/api/DesignElementHandle.java
return (ModuleHandle) getModule( ).getHandle( getModule( ) );
	}
	/**
	 * Returns the element to which this handle is attached.
	 * 
	 * @return The attached element. Will be null if the handle is not attached.
	 */
	public abstract DesignElement getElement( );
	/**
	 * Gets the definition of the element. The definition provides meta-data
	 * about the element, such as its type name, list of defined properties,
	 * list of slots and so on.
	 * 
	 * @return the meta-data definition of the element
	 */
	public IElementDefn getDefn( )
	{
		return getElement( ).getDefn( );
	}
	/**
	 * Returns the value of a property as a generic object. The value is the
	 * internal property value, it is not localized. For a property with the
	 * element reference type, the reference element name is returned.
	 * 
	 * @param propName
	 *            the name of the property of interest
	 * @return the value of the property. The type of the returned object
	 *         depends on the property type.
	 * @see #getIntProperty
	 * @see #getStringProperty