SELECT element: Fix a DCHECK failure after crrev.com/404091

third_party/WebKit/Source/core/html/HTMLSelectElement.cpp

 /*
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
@@ skipping 1970 matching lines @@
     if (layoutObject())
         layoutObject()->updateFromElement();
 }
 
 HTMLOptionElement* HTMLSelectElement::optionToBeShown() const
 {
     if (m_indexToSelectOnCancel >= 0 && static_cast<size_t>(m_indexToSelectOnCancel) < listItems().size() && isHTMLOptionElement(listItems()[m_indexToSelectOnCancel]))
         return toHTMLOptionElement(listItems()[m_indexToSelectOnCancel]);
     if (m_suggestedOption)
         return m_suggestedOption;
+    // TODO(tkent): We should not call optionToBeShown() in multiple() case.
+    if (multiple())
+        return selectedOption();
     DCHECK_EQ(selectedOption(), m_lastOnChangeOption);
     return m_lastOnChangeOption;
 }
 
 void HTMLSelectElement::valueChanged(unsigned listIndex)
 {
     // Check to ensure a page navigation has not occurred while the popup was
     // up.
     Document& doc = document();
     if (&doc != doc.frame()->document())
@@ skipping 137 matching lines @@
 }
 
 void HTMLSelectElement::didMutateSubtree()
 {
     DCHECK(popupIsVisible());
     DCHECK(m_popup);
     m_popup->updateFromElement(PopupMenu::ByDOMChange);
 }
 
 } // namespace blink