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

third_party/WebKit/Source/web/WebHistoryItem.cpp

Index: third_party/WebKit/Source/web/WebHistoryItem.cpp
diff --git a/third_party/WebKit/Source/web/WebHistoryItem.cpp b/third_party/WebKit/Source/web/WebHistoryItem.cpp
index 689741728f813c7b54d0b2d84bda78ab97d7a642..bdd4bf713e7125ea38d96a924fdb731bfd2de856 100644
--- a/third_party/WebKit/Source/web/WebHistoryItem.cpp
+++ b/third_party/WebKit/Source/web/WebHistoryItem.cpp
@@ -184,14 +184,14 @@ WebVector<WebString> WebHistoryItem::getReferencedFilePaths() const {
     for (size_t i = 0; i < formData->elements().size(); ++i) {
       const FormDataElement& element = formData->elements()[i];
       if (element.m_type == FormDataElement::encodedFile)
-        filePaths.add(element.m_filename);
+        filePaths.insert(element.m_filename);
     }
   }
 
   const Vector<String>& referencedFilePaths =
       m_private->getReferencedFilePaths();
   for (size_t i = 0; i < referencedFilePaths.size(); ++i)
-    filePaths.add(referencedFilePaths[i]);
+    filePaths.insert(referencedFilePaths[i]);
 
   Vector<String> results;
   copyToVector(filePaths, results);