Migrate WTF::HashSet::add() to ::insert() [part 1 of N]

third_party/WebKit/Source/core/dom/ElementIntersectionObserverData.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/ElementIntersectionObserverData.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/IntersectionObservation.h"
 #include "core/dom/IntersectionObserver.h"
 #include "core/dom/IntersectionObserverController.h"
 
 namespace blink {
 
 ElementIntersectionObserverData::ElementIntersectionObserverData() {}
 
 IntersectionObservation* ElementIntersectionObserverData::getObservationFor(
     IntersectionObserver& observer) {
   auto i = m_intersectionObservations.find(&observer);
   if (i == m_intersectionObservations.end())
     return nullptr;
   return i->value;
 }
 
 void ElementIntersectionObserverData::addObserver(
     IntersectionObserver& observer) {
-  m_intersectionObservers.add(&observer);
+  m_intersectionObservers.insert(&observer);
 }
 
 void ElementIntersectionObserverData::removeObserver(
     IntersectionObserver& observer) {
   m_intersectionObservers.remove(&observer);
 }
 
 void ElementIntersectionObserverData::addObservation(
     IntersectionObservation& observation) {
   DCHECK(observation.observer());
@@ skipping 33 matching lines @@
   visitor->trace(m_intersectionObservations);
 }
 
 DEFINE_TRACE_WRAPPERS(ElementIntersectionObserverData) {
   for (auto& entry : m_intersectionObservations) {
     visitor->traceWrappers(entry.key);
   }
 }
 
 }  // namespace blink