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
* <li><code>DesignElement.EXTENDS_PROP</code>
	 * </ul>
	 * 
	 * The <code>targetHandle</code> should be in the same report as this
	 * element. And this method should be called in one transaction.
	 * 
	 * @param propName
	 *            name of the property to copy
	 * @param targetHandle
	 *            the target element handle
	 * @throws SemanticException
	 *             if the target element type is not as same as this element
	 *             type, or property is not defined .
	 * @throws IllegalArgumentException
	 *             if the target element is not in the same report as this
	 *             element.
	 */
	public void copyPropertyTo( String propName,
			DesignElementHandle targetHandle ) throws SemanticException
	{
		assert ( targetHandle.getModule( ) == getModule( ) );
		if ( targetHandle.getModule( ) != getModule( ) )
			throw new IllegalArgumentException(
					"The target element should be in the same report !" ); 
		if ( targetHandle.getDefn( ) != getDefn( ) )
			throw new PropertyValueException(
					targetHandle.getDefn( ).getName( ),
					PropertyValueException.DESIGN_EXCEPTION_WRONG_ELEMENT_TYPE,
					PropertyType.ELEMENT_REF_TYPE );
		PropertyDefn propDefn = (ElementPropertyDefn) getDefn( ).getProperty(