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/DesignElementHandle.java
{
		return new ElementFactory( module );
	}
	/**
	 * Returns a property handle for a top-level property. A top-level property
	 * is a property that defines on an element.
	 * 
	 * @param propName
	 *            the name of the property to get
	 * @return The property handle, or <code>null</code> if the no property
	 *         exists with the given name.
	 * @see PropertyHandle
	 */
	public PropertyHandle getPropertyHandle( String propName )
	{
		DesignElement element = getElement( );
		ElementPropertyDefn propDefn = element.getPropertyDefn( propName );
		if ( propDefn == null )
			return null;
		return new PropertyHandle( this, propDefn );
	}
	/**
	 * Returns a user-defined property handle for a top-level property. A
	 * top-level property is a property that defines on an element.
	 * 
	 * @param propName
	 *            the name of the property to get
	 * @return the user property definition handle, or <code>null</code> if
	 *         the no property exists with the given name or it is not a
	 *         user-defined property.