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
updateReference( oldRef, (ElementRefValue) value, prop );
		}
		
		if ( prop.getTypeCode( ) == PropertyType.STRUCT_REF_TYPE )
		{
			StructRefValue oldRef = (StructRefValue) propValues.get( propName );
			updateReference( oldRef, (StructRefValue) value, prop );
		}
		
		if ( value == null )
			propValues.remove( propName );
		else
			propValues.put( propName, value );
	}
	/**
	 * Returns the mask of the given property. If the mask of one property has
	 * not been found, looks for its parent or any ancestor.
	 * <p>
	 * Note that this method is only for internal usage. DO NOT call this method
	 * outside the org.eclipse.birt.report.model package.
	 * 
	 * @param module
	 *            the module
	 * @param propName
	 *            the name of the property
	 * 
	 * @return the mask of the given property
	 */
	public String getPropertyMask( Module module, String propName )
	{