HTMLMediaElement::webMediaPlayer() should never be null if m_readyState >= HAVE_METADATA (multiple …

Source/core/html/HTMLMediaElement.cpp

 /*
  * Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple 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 2703 matching lines @@
 
     if (m_currentSourceNode && source == m_currentSourceNode->nextSibling()) {
         WTF_LOG(Media, "HTMLMediaElement::sourceWasAdded - <source> inserted immediately after current source");
         m_nextChildNodeToConsider = source;
         return;
     }
 
     if (m_nextChildNodeToConsider)
         return;
 
+    if (m_loadState != WaitingForSource)
+        return;
+
     // 4.8.9.5, resource selection algorithm, source elements section:
     // 21. Wait until the node after pointer is a node other than the end of the list. (This step might wait forever.)
     // 22. Asynchronously await a stable state...
     // 23. Set the element's delaying-the-load-event flag back to true (this delays the load event again, in case
     // it hasn't been fired yet).
     setShouldDelayLoadEvent(true);
 
     // 24. Set the networkState back to NETWORK_LOADING.
     m_networkState = NETWORK_LOADING;
 
@@ skipping 939 matching lines @@
 
 #if ENABLE(WEB_AUDIO)
 void HTMLMediaElement::clearWeakMembers(Visitor* visitor)
 {
     if (!visitor->isAlive(m_audioSourceNode) && audioSourceProvider())
         audioSourceProvider()->setClient(0);
 }
 #endif
 
 }