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/ExtendedItem.java
}
	/**
	 * Tests whether the property is just the model property for the extended
	 * element, and its type is XML.
	 * 
	 * @param propName
	 *            the property name to check
	 * @return true if the property is XML type and it is model property for
	 *         extended element, otherwise false
	 */
	public boolean isExtensionXMLProperty( String propName )
	{
		return provider.isExtensionXMLProperty( propName );
	}
	/**
	 * returns the methods defined on this element and defined in the extension
	 * model.
	 * 
	 * @return the method list
	 */
	public List getMethods( )
	{
		if ( methods == null )
			methods = provider.getModelMethodDefns( );
		return methods;
	}
	/**
	 * Returns the script property name of this extended item.
	 * 
	 * @return the script property name