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/command/PropertyCommand.java
(ListingHandle) tmpContainer.getHandle( module ),
							(GroupHandle) element.getHandle( module ),
							groupName );
			if ( !errors.isEmpty( ) )
				return false;
		}
		return true;
	}
	/**
	 * Clears the value of a property.
	 * 
	 * @param propName
	 *            the name of the property to clear.
	 * @throws SemanticException
	 *             if failed to clear property.
	 */
	public void clearProperty( String propName ) throws SemanticException
	{
		setProperty( propName, null );
	}
	/**
	 * Sets the value of the member of a structure.
	 * 
	 * @param ref
	 *            reference to the member to set
	 * @param value
	 *            new value of the member
	 * @throws SemanticException
	 *             if the value is not valid
	 */