Remove unnecessary RAF from tests.

third_party/WebKit/Source/core/dom/IntersectionObserverController.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/dom/IntersectionObserverController.h"
 
 #include "core/dom/Document.h"
 
 namespace blink {
 
@@ skipping 10 matching lines @@
     : ActiveDOMObject(document)
     , m_timer(this, &IntersectionObserverController::deliverIntersectionObservations)
     , m_timerFiredWhileSuspended(false)
 {
 }
 
 IntersectionObserverController::~IntersectionObserverController() { }
 
 void IntersectionObserverController::scheduleIntersectionObserverForDelivery(IntersectionObserver& observer)
 {
-    // TODO(szager): use idle callback with a timeout
+    // TODO(szager): use idle callback with a timeout.  Until we do that, there is no
+    // reliable way to write a test for takeRecords, because it's impossible to guarantee
+    // that javascript will get a chance to run before the timer fires.
     if (!m_timer.isActive())
         m_timer.startOneShot(0, BLINK_FROM_HERE);
     m_pendingIntersectionObservers.add(&observer);
 }
 
 void IntersectionObserverController::resume()
 {
     // If the timer fired while DOM objects were suspended, notifications might be late, so deliver
     // them right away (rather than waiting for m_timer to fire again).
     if (m_timerFiredWhileSuspended) {
@@ skipping 42 matching lines @@
 }
 
 DEFINE_TRACE(IntersectionObserverController)
 {
     visitor->trace(m_trackedIntersectionObservers);
     visitor->trace(m_pendingIntersectionObservers);
     ActiveDOMObject::trace(visitor);
 }
 
 } // namespace blink