Bug 122850 Table/list should not be able to be inserted in Master Page mode.
Description: Table/list should not be able to be inserted in Master Page mode. Steps to reproduce: 1. New a report and transfer to Master Page mode. 2. New a datasource and dataset 3. Drag a list/table to page header/footer, bind it to dataset and drag some columns inside. 4. Save and preview Expected result: Insert list/table item in master page should be forbidden. Actual result: They are allowed and preview showed "undefine" in page
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/util/ModelUtil.java
{
		assert element != null;
		
		DesignElement parent = element.getExtendsElement( );
		if ( parent == null )
			return Collections.EMPTY_MAP;
		Map idMap = new HashMap( );
		Iterator parentIter = new ContentIterator( parent );
		Iterator childIter = new ContentIterator( element );
		while ( childIter.hasNext( ) )
		{
			DesignElement virtualParent = (DesignElement) parentIter.next( );
			DesignElement virtualChild = (DesignElement) childIter.next( );
			assert virtualChild.getDefn( ).getName( ) == virtualChild.getDefn( )
					.getName( );
			assert virtualParent.getID( ) > 0;
			idMap.put( new Long( virtualParent.getID( ) ), virtualChild );
		}
		return idMap;
	}
	/**
	 * Duplicates the structure from one element to another element. Local
	 * properties will all be cleared.Please note that the containment
	 * relationship is kept while property values are not copied.
	 * <p>
	 * The two element should be the same type.
	 * 
	 * @param source
	 *            source element
	 * @param target