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 getElement().isTemplateParameterValue( getModule( ) );
	}
	/**
	 * Gets the property data for either a system-defined or user-defined
	 * property.
	 * 
	 * @param propName
	 *            The name of the property to lookup.
	 * @return The property definition, or null, if the property is undefined.
	 */
	public IElementPropertyDefn getPropertyDefn( String propName )
	{
		
		return getElement( ).getPropertyDefn( propName );
	}
	/**
	 * Returns the effective module of the element. If the element is attached
	 * to the design/library, the design/library is returned. Otherwise, the
	 * module cached in the <code>DesignElementHandle</code> is returned.
	 * 
	 * @return the effective module of the element. Can be null.
	 */
	protected Module getEffectiveModule( )
	{
		return module;
	}
	/**
	 * Returns the overridden value of the specified property given its internal
	 * name.