Bug 146481 Name is not necessary for extended element
Steps to reproduce: 1.New a label named "label" in library 2.New a report, extend lib.label Expected result: No name for the extended label Actual result: "label" is added as the name of label in report. It's not reasonable because "Restore Properties" is enabled even without properties change.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/SimpleGroupElementHandle.java
public boolean isSameType( )
	{
		if ( elements.size( ) == 0 )
			return false;
		IElementDefn baseDefn = null;
		for ( int i = 0; i < elements.size( ); i++ )
		{
			Object item = elements.get( i );
			if ( !( item instanceof DesignElementHandle ) )
				return false;
			IElementDefn elemDefn = ( (DesignElementHandle) item ).getDefn( );
			if ( baseDefn == null )
				baseDefn = elemDefn;
			if ( elemDefn != baseDefn )
				return false;
		}
		return true;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.api.GroupElementHandle#visiblePropertyIterator()
	 */
	public Iterator visiblePropertyIterator( )
	{
		List list = getCommonProperties( );
		final List visibleList = new ArrayList( );
		for ( int i = 0; i < list.size( ); i++ )
		{
			IElementPropertyDefn propDefn = (IElementPropertyDefn) list.get( i );