Bug 142432 MasterPage from library can't be restored to modify
Details: MasterPage from library can't be restored to modify Step: 1.New a library named lib1, and insert a masterpage named lib-mp. 2.Publish the library into resource folder. 3.New a report design and use lib1. 4.Drop the lib-mp from library explorer into outline of report design. 5.Double click lib-mp, and switch to Property editro tab. 6.Click restore. Actual result: Pop up an error message and said that the master page cannot specify size the page type is not custom.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/SimpleGroupElementHandle.java
*            a list of handles of design elements. If a item is not
	 *            <code>DesignElementHandle</code>, it is ignored.
	 * @see DesignElementHandle
	 */
	public SimpleGroupElementHandle( ModuleHandle moduleHandle, List elements )
	{
		assert moduleHandle != null;
		module = moduleHandle.getModule( );
		assert elements != null;
		this.elements = elements;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.api.GroupElementHandle#getElements()
	 */
	public List getElements( )
	{
		return elements;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.api.GroupElementHandle#getModule()
	 */
	public Module getModule( )
	{
		return module;
	}
	/*