Ensure style resolver is created to avoid crash.

Source/core/dom/ContainerNode.cpp

 /*
  * 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, 2008, 2009 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.
@@ skipping 801 matching lines @@
 void ContainerNode::focusStateChanged()
 {
     // If we're just changing the window's active state and the focused node has no
     // renderer we can just ignore the state change.
     if (!renderer())
         return;
 
     if (renderStyle()->affectedByFocus() && renderStyle()->hasPseudoStyle(FIRST_LETTER))
         setNeedsStyleRecalc(SubtreeStyleChange);
     else if (isElementNode() && toElement(this)->childrenAffectedByFocus())
-        document().styleResolver()->ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoFocus, *toElement(this));
+        document().ensureStyleResolver().ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoFocus, *toElement(this));
     else if (renderStyle()->affectedByFocus())
         setNeedsStyleRecalc(LocalStyleChange);
 
     if (renderer() && renderer()->style()->hasAppearance())
         RenderTheme::theme().stateChanged(renderer(), FocusState);
 }
 
 void ContainerNode::setFocus(bool received)
 {
     if (focused() == received)
         return;
 
     Node::setFocus(received);
 
     focusStateChanged();
 
     if (renderer() || received)
         return;
 
     // If :focus sets display: none, we lose focus but still need to recalc our style.
     if (isElementNode() && toElement(this)->childrenAffectedByFocus())
-        document().styleResolver()->ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoFocus, *toElement(this));
+        document().ensureStyleResolver().ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoFocus, *toElement(this));
     else
         setNeedsStyleRecalc(LocalStyleChange);
 }
 
 void ContainerNode::setActive(bool down)
 {
     if (down == active())
         return;
 
     Node::setActive(down);
 
     // FIXME: Why does this not need to handle the display: none transition like :hover does?
     if (renderer()) {
         if (renderStyle()->affectedByActive() && renderStyle()->hasPseudoStyle(FIRST_LETTER))
             setNeedsStyleRecalc(SubtreeStyleChange);
         else if (isElementNode() && toElement(this)->childrenAffectedByActive())
-            document().styleResolver()->ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoActive, *toElement(this));
+            document().ensureStyleResolver().ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoActive, *toElement(this));
         else if (renderStyle()->affectedByActive())
             setNeedsStyleRecalc(LocalStyleChange);
 
         if (renderStyle()->hasAppearance())
             RenderTheme::theme().stateChanged(renderer(), PressedState);
     }
 }
 
 void ContainerNode::setHovered(bool over)
 {
     if (over == hovered())
         return;
 
     Node::setHovered(over);
 
     // If :hover sets display: none we lose our hover but still need to recalc our style.
     if (!renderer()) {
         if (over)
             return;
         if (isElementNode() && toElement(this)->childrenAffectedByHover())
-            document().styleResolver()->ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoHover, *toElement(this));
+            document().ensureStyleResolver().ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoHover, *toElement(this));
         else
             setNeedsStyleRecalc(LocalStyleChange);
         return;
     }
 
     if (renderStyle()->affectedByHover() && renderStyle()->hasPseudoStyle(FIRST_LETTER))
         setNeedsStyleRecalc(SubtreeStyleChange);
     else if (isElementNode() && toElement(this)->childrenAffectedByHover())
-        document().styleResolver()->ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoHover, *toElement(this));
+        document().ensureStyleResolver().ensureUpdatedRuleFeatureSet().scheduleStyleInvalidationForPseudoChange(CSSSelector::PseudoHover, *toElement(this));
     else if (renderStyle()->affectedByHover())
         setNeedsStyleRecalc(LocalStyleChange);
 
     if (renderer()->style()->hasAppearance())
         RenderTheme::theme().stateChanged(renderer(), HoverState);
 }
 
 PassRefPtr<HTMLCollection> ContainerNode::children()
 {
     return ensureRareData().ensureNodeLists().addCache<HTMLCollection>(*this, NodeChildren);
@@ skipping 295 matching lines @@
         return true;
 
     if (node->isElementNode() && toElement(node)->shadow())
         return true;
 
     return false;
 }
 #endif
 
 } // namespace WebCore