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

third_party/WebKit/Source/modules/time_zone_monitor/TimeZoneMonitorClient.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 "modules/time_zone_monitor/TimeZoneMonitorClient.h"
 
 #include "bindings/core/v8/V8Binding.h"
 #include "bindings/core/v8/V8PerIsolateData.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/workers/WorkerBackingThread.h"
@@ skipping 55 matching lines @@
   HashSet<WorkerBackingThread*> posted;
   for (WorkerThread* thread : threads) {
     // Ensure every WorkerBackingThread(holding one platform thread) only get
     // the task posted once, because one WorkerBackingThread could be shared
     // among multiple WorkerThreads.
     if (posted.contains(&thread->workerBackingThread()))
       continue;
     thread->postTask(BLINK_FROM_HERE,
                      crossThreadBind(&NotifyTimezoneChangeOnWorkerThread,
                                      WTF::crossThreadUnretained(thread)));
-    posted.add(&thread->workerBackingThread());
+    posted.insert(&thread->workerBackingThread());
   }
 }
 
 }  // namespace blink