Move Node::retarget() to TreeScope::retarget()

third_party/WebKit/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 402 matching lines @@
     DCHECK(this);
     DCHECK(!node.isDocumentNode());
 #if !ENABLE(OILPAN)
     ASSERT_WITH_SECURITY_IMPLICATION(!node.m_deletionHasBegun);
 #endif
     TreeScopeAdopter adopter(node, *this);
     if (adopter.needsScopeChange())
         adopter.execute();
 }
 
+Element* TreeScope::retarget(const Element& target) const
+{
+    for (const Element* ancestor = ⌖ ancestor; ancestor = ancestor->shadowHost()) {
+        if (this == ancestor->treeScope())
+            return const_cast<Element*>(ancestor);
+    }
+    return nullptr;
+}
+
 Element* TreeScope::adjustedFocusedElement() const
 {
     Document& document = rootNode().document();
     Element* element = document.focusedElement();
     if (!element && document.page())
         element = document.page()->focusController().focusedFrameOwnerElement(*document.frame());
     if (!element)
         return nullptr;
 
     if (rootNode().isInV1ShadowTree()) {
-        if (Node* retargeted = rootNode().retarget(*element)) {
-            DCHECK(retargeted->isElementNode());
-            return this == &retargeted->treeScope() ? toElement(retargeted) : nullptr;
+        if (Element* retargeted = retarget(*element)) {
+            return (this == &retargeted->treeScope()) ? retargeted : nullptr;

[kochi, 2016/04/15 05:40:46]

Is there any chance that the result of retarget() is in a different tree scope?
If not the body for outer if is just "return retargeted(*element);".

[hayato, 2016/04/15 07:30:52]

Let me leave this as is.

I am aware that the current Node::retarget does not match the spec, though the
current behavior is enough for adjustedFocusedElement.

I will update the TreeScope::retarget() in another patch with a layout test, to
make it match the spec.

         }
         return nullptr;
     }
 
     EventPath* eventPath = new EventPath(*element);
     for (size_t i = 0; i < eventPath->size(); ++i) {
         if (eventPath->at(i).node() == rootNode()) {
             // eventPath->at(i).target() is one of the followings:
             // - InsertionPoint
             // - shadow host
@@ skipping 138 matching lines @@
     visitor->trace(m_idTargetObserverRegistry);
     visitor->trace(m_selection);
     visitor->trace(m_elementsById);
     visitor->trace(m_imageMapsByName);
     visitor->trace(m_labelsByForAttribute);
     visitor->trace(m_scopedStyleResolver);
     visitor->trace(m_radioButtonGroupScope);
 }
 
 } // namespace blink