Bug 152430 Key can modify to empty string
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/PropertyCommand.java
*/
	private void setIntrinsicProperty( ElementPropertyDefn prop, Object value )
			throws SemanticException
	{
		String propName = prop.getName( );
		if ( DesignElement.NAME_PROP.equals( propName ) )
		{
			String name = (String) value;
			NameCommand cmd = new NameCommand( module, element );
			cmd.setName( name );
		}
		else if ( DesignElement.EXTENDS_PROP.equals( propName ) )
		{
			ExtendsCommand cmd = new ExtendsCommand( module, element );
			cmd.setExtendsRefValue( (ElementRefValue) value );
		}
		else if ( StyledElement.STYLE_PROP.equals( propName ) )
		{
			
			StyleCommand cmd = new StyleCommand( module, element );
			cmd.setStyleRefValue( (ElementRefValue) value );
		}
		else if ( ReportDesign.UNITS_PROP.equals( propName ) )
		{
			doSetProperty( prop, value );
		}
		else if ( IExtendedItemModel.EXTENSION_NAME_PROP.equals( propName ) )
		{
			doSetProperty( prop, value );
		}