Bug 136241 [regression]Preview template in web viewer and pdf didn't get correct effect.
Description: Preview template items in web viewer and pdf didn't get correct effect. Steps to reproduce: 1. Create template items. 2. Preview in Web Viewer and pdf. Expected result: Same effect as in html. Actual result: In web viewer, see only blank box. In pdf, blank page.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
* have been enforced by the application prior to calling this method.
	 * <p>
	 * Part of: User-defined property system.
	 * 
	 * @param userProp
	 *            definition of the user-defined property
	 */
	public void addUserPropertyDefn( UserPropertyDefn userProp )
	{
		assert getDefn( ).allowsUserProperties( );
		assert userProp != null;
		String propName = userProp.getName( );
		assert getUserPropertyDefn( propName ) == null;
		assert getDefn( ).getProperty( propName ) == null;
		if ( userProperties == null )
			userProperties = new LinkedHashMap( );
		userProperties.put( propName, userProp );
	}
	/**
	 * Drops a user-defined property. The application must have previously
	 * removed all existing values for that property. The application must have
	 * previously validated that the user-defined property does exist, and is
	 * defined on this element.
	 * <p>
	 * Part of: User-defined property system.
	 * 
	 * @param prop
	 *            The user-defined property.
	 */
	public void dropUserPropertyDefn( UserPropertyDefn prop )