// get the form name
String formName = getParentFormName(context);
URLEncoder encoder = context.getURLEncoder();
String sourceKey = encoder.encodeParameter( SOURCE_PARAM );
FormValueRenderer.addNeededValue(context, formName, sourceKey);
// BUG 3557710 - FORM ENCODER AND POSTBACK HANDLING
FormEncoder formEncoder = context.getFormEncoder();
String encodedSource =