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

third_party/WebKit/Source/core/css/ActiveStyleSheets.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/css/ActiveStyleSheets.h"
 
 #include "core/css/CSSStyleSheet.h"
 #include "core/css/RuleSet.h"
 #include "core/css/resolver/ScopedStyleResolver.h"
 #include "core/dom/ContainerNode.h"
@@ skipping 14 matching lines @@
 
   // Walk the common prefix of stylesheets. If the stylesheet rules were
   // modified since last time, add them to the list of changed rulesets.
   for (; index < minCount &&
          newStyleSheets[index].first == oldStyleSheets[index].first;
        index++) {
     if (newStyleSheets[index].second == oldStyleSheets[index].second)
       continue;
 
     if (newStyleSheets[index].second)
-      changedRuleSets.add(newStyleSheets[index].second);
+      changedRuleSets.insert(newStyleSheets[index].second);
     if (oldStyleSheets[index].second)
-      changedRuleSets.add(oldStyleSheets[index].second);
+      changedRuleSets.insert(oldStyleSheets[index].second);
   }
 
   if (index == oldStyleSheetCount) {
     // The old stylesheet vector is a prefix of the new vector in terms of
     // StyleSheets. If none of the RuleSets changed, we only need to add the new
     // sheets to the ScopedStyleResolver (ActiveSheetsAppended).
     bool ruleSetsChangedInCommonPrefix = !changedRuleSets.isEmpty();
     for (; index < newStyleSheetCount; index++) {
       if (newStyleSheets[index].second)
         changedRuleSets.add(newStyleSheets[index].second);
@@ skipping 53 matching lines @@
     if (sheet1.second)
       changedRuleSets.add(sheet1.second);
     if (sheet2.second)
       changedRuleSets.add(sheet2.second);
   }
   return changedRuleSets.isEmpty() ? NoActiveSheetsChanged
                                    : ActiveSheetsChanged;
 }
 
 }  // namespace blink