Explore the possibility of implementing the CSS Region interface.

Source/core/dom/PseudoElement.cpp

 /*
  * Copyright (C) 2012 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 39 matching lines @@
         return before;
     default:
         return emptyString();
     }
 }
 
 PseudoElement::PseudoElement(Element* parent, PseudoId pseudoId)
     : Element(pseudoElementTagName(), &parent->document(), CreatePseudoElement)
     , m_pseudoId(pseudoId)
 {
+    ScriptWrappable::init(this);
+
     ASSERT(pseudoId != NOPSEUDO);
     setParentOrShadowHostNode(parent);
     setHasCustomStyleCallbacks();
 }
 
 PassRefPtr<RenderStyle> PseudoElement::customStyleForRenderer()
 {
     return parentOrShadowHostElement()->renderer()->getCachedPseudoStyle(m_pseudoId);
 }
 
@@ skipping 44 matching lines @@
 
         // The style for the RenderTextFragment for first letter is managed by an enclosing block, not by us.
         if (child->style()->styleType() == FIRST_LETTER)
             continue;
 
         child->setPseudoStyle(renderer->style());
     }
 }
 
 } // namespace