Migrate WTF::Vector::append() to ::push_back() [part 13 of N]

third_party/WebKit/Source/modules/indexeddb/IDBObserver.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/indexeddb/IDBObserver.h"
 
 #include <bitset>
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/modules/v8/IDBObserverCallback.h"
@@ skipping 71 matching lines @@
                             ExceptionState& exceptionState) {
   if (!database->backend()) {
     exceptionState.throwDOMException(InvalidStateError,
                                      IDBDatabase::databaseClosedErrorMessage);
     return;
   }
 
   Vector<int32_t> observerIdsToRemove;
   for (const auto& it : m_observerIds) {
     if (it.value == database)
-      observerIdsToRemove.append(it.key);
+      observerIdsToRemove.push_back(it.key);
   }
   m_observerIds.removeAll(observerIdsToRemove);
 
   if (!observerIdsToRemove.isEmpty())
     database->removeObservers(observerIdsToRemove);
 }
 
 DEFINE_TRACE(IDBObserver) {
   visitor->trace(m_callback);
   visitor->trace(m_observerIds);
 }
 
 }  // namespace blink