Bug 153040 Template definition should be removed after the report item is deleted
Steps to reproduce: 1.New a report, extends lib.label 2.Convert the label to template report item, and revert it back to the report item 3.Delete the label 4.Remove the included library Expected result: Library can be removed Actual result: A BIRT exception occurred. Plug-in Provider:Eclipse.org Plug-in Name:BIRT Model Plug-in ID:org.eclipse.birt.report.model Version:2.1.0.v20060808-0630 Error Code:Error.LibraryException.LIBRARY_HAS_DESCENDENTS Error Message:The library "Lib" can no be dropped because it has descendents "NewLabel" in the current module.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/core/UserPropertyDefn.java
* 
	 * @param typeDefn
	 *            the property type
	 */
	public void setType( PropertyType typeDefn )
	{
		type = typeDefn;
	}
	/**
	 * Checks whether the element can take the given user property definition
	 * and the definition is valid.
	 * 
	 * @param module
	 *            the module
	 * @param element
	 *            the design element that holds the user-defined property
	 * 
	 * @throws UserPropertyException
	 *             if the element is not allowed to have user property or the
	 *             user property definition is invalid.
	 * @throws MetaDataException
	 *             if the user property definition is inconsistent.
	 */
	public void checkUserPropertyDefn( Module module, DesignElement element )
			throws UserPropertyException, MetaDataException
	{
		
		String name = getName( );
		if ( !element.getDefn( ).allowsUserProperties( ) )
			throw new UserPropertyException( element, name,