Skip removal of stylesheet candidate node if not added.

Source/core/dom/StyleElement.cpp

 /*
  * Copyright (C) 2006, 2007 Rob Buis
  * Copyright (C) 2008 Apple, Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 96 matching lines @@
         clearSheet(element);
     if (removedSheet)
         document.removedStyleSheet(removedSheet.get(), AnalyzedStyleUpdate);
 }
 
 void StyleElement::clearDocumentData(Document& document, Element* element)
 {
     if (m_sheet)
         m_sheet->clearOwnerNode();
 
-    if (element->inDocument()) {
-        // HTMLLinkElement in shadow tree is not supported.
-        TreeScope& treeScope = isHTMLStyleElement(element) || isSVGStyleElement(element) ? element->treeScope() : element->document();
-        document.styleEngine().removeStyleSheetCandidateNode(element, treeScope);
+    if (m_registeredAsCandidate) {
+        ASSERT(element->inDocument());
+        document.styleEngine().removeStyleSheetCandidateNode(element, element->treeScope());
     }
 }
 
 void StyleElement::childrenChanged(Element* element)
 {
     ASSERT(element);
     if (m_createdByParser)
         return;
 
     process(element);
@@ skipping 92 matching lines @@
 {
     document.styleEngine().addPendingSheet();
 }
 
 DEFINE_TRACE(StyleElement)
 {
     visitor->trace(m_sheet);
 }
 
 }