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/metadata/ElementPropertyDefn.java
* @return the method information of this property. Return null, if this
	 *         property is not a method property.
	 */
	public IMethodInfo getMethodInfo( )
	{
		if ( getTypeCode( ) == IPropertyType.SCRIPT_TYPE )
			return (IMethodInfo) details;
		return null;
	}
	/**
	 * Returns <code>true</code> indicating if the xml property value
	 * represents the extesion-defined model.
	 * 
	 * @return <code>true</code> if the xml property value represents the
	 *         extesion-defined model.
	 */
	public boolean hasOwnModel( )
	{
		return false;
	}
	/**
	 * Gets useOwnModel property value.
	 * 
	 * @return useOwnModel property value.
	 */
	public boolean isUseOwnModel( )
	{
		return useOwnModel;
	}
}