void guardedCall(Runnable r) {
        if (outstanding.compareAndSet(false,true)) {
            try {
                r.run();
            } finally {
                outstanding.set(false);
            }

        }
    }
Method to guard from multiple invocations. Used to fix #708
@param r runnable
runtime-parent/runtime-core/src/main/java/com/speedment/runtime/core/internal/component/StatisticsReporterSchedulerComponentImpl.java