Merge 115763

Source/WebCore/html/parser/HTMLTreeBuilder.cpp

 /*
  * Copyright (C) 2010 Google, Inc. All Rights Reserved.
  * Copyright (C) 2011 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
@@ skipping 2186 matching lines @@
                 AtomicHTMLToken endSelect(HTMLTokenTypes::EndTag, selectTag.localName());
                 processEndTag(endSelect);
                 processEndTag(token);
             }
             return;
         }
         // Fall through.
     case InSelectMode:
         ASSERT(insertionMode() == InSelectMode || insertionMode() == InSelectInTableMode);
         if (token.name() == optgroupTag) {
-            if (m_tree.currentNode()->hasTagName(optionTag) && m_tree.oneBelowTop()->hasTagName(optgroupTag))
+            if (m_tree.currentNode()->hasTagName(optionTag) && m_tree.oneBelowTop() && m_tree.oneBelowTop()->hasTagName(optgroupTag))
                 processFakeEndTag(optionTag);
             if (m_tree.currentNode()->hasTagName(optgroupTag)) {
                 m_tree.openElements()->pop();
                 return;
             }
             parseError(token);
             return;
         }
         if (token.name() == optionTag) {
             if (m_tree.currentNode()->hasTagName(optionTag)) {
@@ skipping 612 matching lines @@
 }
 
 bool HTMLTreeBuilder::pluginsEnabled(Frame* frame)
 {
     if (!frame)
         return false;
     return frame->loader()->subframeLoader()->allowPlugins(NotAboutToInstantiatePlugin);
 }
 
 }