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

Source/core/html/track/TextTrackCueList.cpp

 /*
  * Copyright (C) 2011 Google Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 33 matching lines @@
     return m_list.find(cue);
 }
 
 TextTrackCue* TextTrackCueList::item(unsigned index) const
 {
     if (index < m_list.size())
         return m_list[index].get();
     return 0;
 }
 
-TextTrackCue* TextTrackCueList::getCueById(const String& id) const
+TextTrackCue* TextTrackCueList::getCueById(const AtomicString& id) const
 {
     for (size_t i = 0; i < m_list.size(); ++i) {
         if (m_list[i]->id() == id)
             return m_list[i].get();
     }
     return 0;
 }
 
 TextTrackCueList* TextTrackCueList::activeCues()
 {
@@ skipping 72 matching lines @@
 }
 
 void TextTrackCueList::invalidateCueIndexes(size_t start)
 {
     for (size_t i = start; i < m_list.size(); ++i)
         m_list[i]->invalidateCueIndex();
 }
 
 } // namespace WebCore