Fix potential null pointer access in HTMLMediaElement::seek

third_party/WebKit/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 1672 matching lines @@
     WTF_LOG(Media, "HTMLMediaElement::setIgnorePreloadNone(%p)", this);
     m_ignorePreloadNone = true;
     setPlayerPreload();
 }
 
 void HTMLMediaElement::seek(double time)
 {
     WTF_LOG(Media, "HTMLMediaElement::seek(%p, %f)", this, time);
 
     // 2 - If the media element's readyState is HAVE_NOTHING, abort these steps.
-    if (m_readyState == HAVE_NOTHING)
+    // FIXME: remove m_webMediaPlayer check once we figure out how
+    // m_webMediaPlayer is going out of sync with readystate.
+    // m_webMediaPlayer is cleared but readystate is not set to HAVE_NOTHING.
+    if (!m_webMediaPlayer || m_readyState == HAVE_NOTHING)
         return;
 
     // Ignore preload none and start load if necessary.
     setIgnorePreloadNone();
 
     // Get the current time before setting m_seeking, m_lastSeekTime is returned once it is set.
     refreshCachedTime();
     // This is needed to avoid getting default playback start position from currentTime().
     double now = m_cachedTime;
 
@@ skipping 2161 matching lines @@
 
 IntRect HTMLMediaElement::AutoplayHelperClientImpl::absoluteBoundingBoxRect() const
 {
     IntRect result;
     if (LayoutObject* object = m_element->layoutObject())
         result = object->absoluteBoundingBoxRect();
     return result;
 }
 
 } // namespace blink