Bug 213680 [2.2.2]Chart script can not be cleaned completely.
Description: Reset script or delete all script does not work. build version: v20071221-0630 steps to reproduce: 1. New a report. 2. New a chart. 3. Enter some script for the chart and save the report. 4. Click the reset scirpt button or delete all script. 5. Save the report and switch to layout,then switch back to script page. Expected result: Script are cleaned. Actual result: Script are not cleaned. Note: If you delete part of the script, it works.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/elements/strategy/ExtendedItemPropSearchStrategy.java
}
	/**
	 * Gets a property value given its definition. This version does the
	 * property search with style reference, extends reference and containment.
	 * The default value style property defined in session is also searched, but
	 * the default value defined in ROM will not be returned.
	 * 
	 * @param module
	 *            the module
	 * @param element
	 *            the element to start search
	 * @param prop
	 *            definition of the property to get
	 * @return The property value, or null if no value is set.
	 */
	public Object getPropertyExceptRomDefault( Module module,
			DesignElement element, ElementPropertyDefn prop )
	{
		assert element instanceof ExtendedItem;
		ExtendedItem extendedItem = (ExtendedItem) element;
		
		ElementPropertyDefn propDefn = extendedItem.getPropertyDefn( prop
				.getName( ) );;
		if ( propDefn != null )
		{
			boolean useOwnModel = propDefn.isUseOwnModel( );
			if ( useOwnModel )
			{
				IReportItem reportItem = extendedItem.getExtendedElement( );
				if ( reportItem != null )