Revert of Remove unnecessary uses of GarbageCollectedFinalized<>.

third_party/WebKit/Source/core/dom/NodeIntersectionObserverData.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/NodeIntersectionObserverData.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/IntersectionObservation.h"
 #include "core/dom/IntersectionObserver.h"
 #include "core/dom/IntersectionObserverController.h"
 
 namespace blink {
 
 NodeIntersectionObserverData::NodeIntersectionObserverData() { }
 
+NodeIntersectionObserverData::~NodeIntersectionObserverData() { }
+
 IntersectionObservation* NodeIntersectionObserverData::getObservationFor(IntersectionObserver& observer)
 {
     auto i = m_intersectionObservations.find(&observer);
     if (i == m_intersectionObservations.end())
         return nullptr;
     return i->value;
 }
 
 void NodeIntersectionObserverData::addObservation(IntersectionObservation& observation)
 {
@@ skipping 17 matching lines @@
     node.document().ensureIntersectionObserverController().removeTrackedObserversForRoot(node);
 }
 
 DEFINE_TRACE(NodeIntersectionObserverData)
 {
     visitor->trace(m_intersectionObservers);
     visitor->trace(m_intersectionObservations);
 }
 
 } // namespace blink