Make calls to AtomicString(const String&) explicit in dom/

Source/core/events/EventTarget.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  *           (C) 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ skipping 171 matching lines @@
     event->setEventPhase(Event::AT_TARGET);
     bool defaultPrevented = fireEventListeners(event.get());
     event->setEventPhase(0);
     return defaultPrevented;
 }
 
 void EventTarget::uncaughtExceptionInEventHandler()
 {
 }
 
-static AtomicString legacyType(const Event* event)
+static const AtomicString& legacyType(const Event* event)
 {
     if (event->type() == EventTypeNames::transitionend)
         return EventTypeNames::webkitTransitionEnd;
 
     if (event->type() == EventTypeNames::animationstart)
         return EventTypeNames::webkitAnimationStart;
 
     if (event->type() == EventTypeNames::animationend)
         return EventTypeNames::webkitAnimationEnd;
 
     if (event->type() == EventTypeNames::animationiteration)
         return EventTypeNames::webkitAnimationIteration;
 
     if (event->type() == EventTypeNames::wheel)
         return EventTypeNames::mousewheel;
 
-    return emptyString();
+    return emptyAtom;
 }
 
 void EventTarget::countLegacyEvents(const AtomicString& legacyTypeName, EventListenerVector* listenersVector, EventListenerVector* legacyListenersVector)
 {
     UseCounter::Feature unprefixedFeature;
     UseCounter::Feature prefixedFeature;
     UseCounter::Feature prefixedAndUnprefixedFeature;
     bool shouldCount = false;
 
     if (legacyTypeName == EventTypeNames::webkitTransitionEnd) {
@@ skipping 148 matching lines @@
     // they have one less listener to invoke.
     if (d->firingEventIterators) {
         for (size_t i = 0; i < d->firingEventIterators->size(); ++i) {
             d->firingEventIterators->at(i).iterator = 0;
             d->firingEventIterators->at(i).end = 0;
         }
     }
 }
 
 } // namespace WebCore