Make TreeScope::baseURL pure virtual

Source/core/dom/TreeScope.cpp

 /*
  * Copyright (C) 2011 Google Inc. All Rights Reserved.
  * Copyright (C) 2012 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 477 matching lines @@
 {
     for (Element* element = ElementTraversal::firstWithin(*rootNode()); element; element = ElementTraversal::nextIncludingPseudo(*element)) {
         for (ShadowRoot* root = element->youngestShadowRoot(); root; root = root->olderShadowRoot())
             root->setNeedsStyleRecalcForViewportUnits();
         RenderStyle* style = element->renderStyle();
         if (style && style->hasViewportUnits())
             element->setNeedsStyleRecalc(LocalStyleChange);
     }
 }
 
+const KURL& TreeScope::baseURL() const
+{
+    if (!m_baseURL.isEmpty() || document() == this)

[esprehn, 2014/01/14 00:36:36]

Why not just make this virtual and let document override it?

+        return m_baseURL;
+    return document().baseURL();
+}
+
 KURL TreeScope::completeURL(const String& url) const
 {
     return document().completeURLWithOverride(url, baseURL());
 }
 
 } // namespace WebCore