void DOMTimer::fired()
{
    ExecutionContext* context = getExecutionContext();
    ASSERT(context);
    context->timers()->setTimerNestingLevel(m_nestingLevel);
    ASSERT(!context->activeDOMObjectsAreSuspended());
    // Only the first execution of a multi-shot timer should get an affirmative user gesture indicator.
    UserGestureIndicator gestureIndicator(m_userGestureToken.release());

    TRACE_EVENT1("devtools.timeline", "TimerFire", "data", InspectorTimerFireEvent::data(context, m_timeoutID));
    InspectorInstrumentationCookie cookie = InspectorInstrumentation::willFireTimer(context, m_timeoutID);

    // Simple case for non-one-shot timers.
    if (isActive()) {
        if (repeatInterval() && repeatInterval() < minimumInterval) {
            m_nestingLevel++;
            if (m_nestingLevel >= maxTimerNestingLevel)
                augmentRepeatInterval(minimumInterval - repeatInterval());
        }

        // No access to member variables after this point, it can delete the timer.
        m_action->execute(context);

        InspectorInstrumentation::didFireTimer(cookie);

        return;
    }

    RawPtr<DOMTimer> protect(this);

    // Unregister the timer from ExecutionContext before executing the action
    // for one-shot timers.
    RawPtr<ScheduledAction> action = m_action.release();
    context->timers()->removeTimeoutByID(m_timeoutID);

    action->execute(context);

    InspectorInstrumentation::didFireTimer(cookie);
    TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "UpdateCounters", TRACE_EVENT_SCOPE_THREAD, "data", InspectorUpdateCountersEvent::data());

    // ExecutionContext might be already gone when we executed action->execute().
    if (getExecutionContext())
        getExecutionContext()->timers()->setTimerNestingLevel(0);
}