WTF::notFound looks too much like a local variable.

Source/core/platform/mediastream/MediaStreamSource.cpp

 /*
  * Copyright (C) 2012 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
@@ skipping 48 matching lines @@
 }
 
 void MediaStreamSource::addObserver(MediaStreamSource::Observer* observer)
 {
     m_observers.append(observer);
 }
 
 void MediaStreamSource::removeObserver(MediaStreamSource::Observer* observer)
 {
     size_t pos = m_observers.find(observer);
-    if (pos != notFound)
+    if (pos != kNotFound)
         m_observers.remove(pos);
 }
 
 void MediaStreamSource::addAudioConsumer(PassRefPtr<AudioDestinationConsumer> consumer)
 {
     ASSERT(m_requiresConsumer);
     MutexLocker locker(m_audioConsumersLock);
     m_audioConsumers.append(consumer);
 }
 
 bool MediaStreamSource::removeAudioConsumer(AudioDestinationConsumer* consumer)
 {
     ASSERT(m_requiresConsumer);
     MutexLocker locker(m_audioConsumersLock);
     size_t pos = m_audioConsumers.find(consumer);
-    if (pos != notFound) {
+    if (pos != kNotFound) {
         m_audioConsumers.remove(pos);
         return true;
     }
     return false;
 }
 
 void MediaStreamSource::setAudioFormat(size_t numberOfChannels, float sampleRate)
 {
     ASSERT(m_requiresConsumer);
     MutexLocker locker(m_audioConsumersLock);
     for (Vector<RefPtr<AudioDestinationConsumer> >::iterator it = m_audioConsumers.begin(); it != m_audioConsumers.end(); ++it)
         (*it)->setFormat(numberOfChannels, sampleRate);
 }
 
 void MediaStreamSource::consumeAudio(AudioBus* bus, size_t numberOfFrames)
 {
     ASSERT(m_requiresConsumer);
     MutexLocker locker(m_audioConsumersLock);
     for (Vector<RefPtr<AudioDestinationConsumer> >::iterator it = m_audioConsumers.begin(); it != m_audioConsumers.end(); ++it)
         (*it)->consumeAudio(bus, numberOfFrames);
 }
 
 } // namespace WebCore