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/extension/PeerExtensibilityProvider.java
* extensible while the value is invalid.
	 * 
	 * @param propName
	 * @param value
	 */
	abstract public void handleInvalidPropertyValue( String propName,
			Object value );
	/**
	 * Handles undefined property. The property definition is not found.
	 * 
	 * @param propName
	 * @param value
	 */
	abstract public void handleUndefinedProperty( String propName, Object value );
	/**
	 * Handles undefined children. The child is not allowed to be inserted to
	 * the container.
	 * 
	 * @param propName
	 * @param child
	 */
	abstract public void handleIllegalChildren( String propName,
			DesignElement child );
	/**
	 * Returns the map for properties that has invalid values.
	 * 
	 * @return
	 */
	abstract public Map getInvalidPropertyValueMap( );
	/**