Merge 88474 - 2011-06-09 Julien Chaffraix <jchaffraix@webkit.org>

Source/WebCore/css/WebKitCSSKeyframesRule.cpp

 /*
  * Copyright (C) 2007, 2008 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 48 matching lines @@
 {
     return m_name;
 }
 
 void WebKitCSSKeyframesRule::setName(const String& name)
 {
     m_name = name;
     
     // Since the name is used in the keyframe map list in CSSStyleSelector, we need
     // to recompute the style sheet to get the updated name.
-    stylesheet()->styleSheetChanged();
+    if (stylesheet())
+        stylesheet()->styleSheetChanged();
 }
 
 unsigned WebKitCSSKeyframesRule::length() const
 {
     return m_lstCSSRules.get()->length();
 }
 
 WebKitCSSKeyframeRule* WebKitCSSKeyframesRule::item(unsigned index)
 {
     CSSRule* rule = m_lstCSSRules.get()->item(index);
@@ skipping 70 matching lines @@
             result += m_lstCSSRules->item(i)->cssText();
             result += "\n";
         }
     }
 
     result += "}";
     return result;
 }
 
 } // namespace WebCore