private static void putGoogleAnalyticsTrackingIdIntoFlowScope(final RequestContext context, final String value) {
        if (StringUtils.isBlank(value)) {
            context.getFlowScope().remove(ATTRIBUTE_FLOWSCOPE_GOOGLE_ANALYTICS_TRACKING_ID);
        } else {
            context.getFlowScope().put(ATTRIBUTE_FLOWSCOPE_GOOGLE_ANALYTICS_TRACKING_ID, value);
        }
    }
Put tracking id into flow scope.

@param context the context
@param value   the value
support/cas-server-support-google-analytics/src/main/java/org/apereo/cas/web/flow/CasGoogleAnalyticsWebflowConfigurer.java