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
{
		setProperty( propName, new Integer( value ) );
	}
	/**
	 * Sets the value of a property to a string. Use this for properties such as
	 * expressions, labels, HTML, or XML. Also use it to set the value of a
	 * choice using the internal string name of the choice. Use it to set the
	 * value of a dimension when using specified units, such as "10pt".
	 * 
	 * @param propName
	 *            the property name
	 * @param value
	 *            the value to set
	 * @throws SemanticException
	 *             if the value of a choice or other property is incorrect.
	 */
	public void setStringProperty( String propName, String value )
			throws SemanticException
	{
		setProperty( propName, value );
	}
	/**
	 * Sets the value of a property to a double. When used for dimension
	 * properties, the units of the dimension are assumed to be in application
	 * units.
	 * 
	 * @param propName
	 *            the property name
	 * @param value
	 *            the value to set