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
* @param propName
	 *            the name of the property of interest
	 * @return the value of the property. The type of the returned object
	 *         depends on the property type.
	 * @see #getIntProperty
	 * @see #getStringProperty
	 * @see #getFloatProperty
	 * @see #getNumberProperty
	 */
	public Object getProperty( String propName )
	{
		
		DesignElement element = getElement( );
		Object value = element.getProperty( module, propName );
		if ( value instanceof ReferenceValue )
			return ReferenceValueUtil.needTheNamespacePrefix(
					(ReferenceValue) value, getModule( ) );
		PropertyDefn defn = (PropertyDefn) getPropertyDefn( propName );
		if ( value instanceof List && defn != null
				&& defn.getSubTypeCode( ) == PropertyType.LIST_TYPE )
		{
			List valueList = (List) value;
			List names = new ArrayList( );
			for ( int i = 0; i < valueList.size( ); i++ )
			{
				ElementRefValue item = (ElementRefValue) valueList.get( i );
				names.add( ReferenceValueUtil.needTheNamespacePrefix( item,
						getModule( ) ) );
			}
			return names;