Clarify a role of Shadow DOM related functions

third_party/WebKit/Source/core/dom/shadow/FlatTreeTraversal.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 85 matching lines @@
     return slot;
 }
 
 // TODO(hayato): This may return a wrong result for a node which is not in a
 // document flat tree.  See FlatTreeTraversalTest's redistribution test for details.
 Node* FlatTreeTraversal::traverseSiblings(const Node& node, TraversalDirection direction)
 {
     if (node.isChildOfV1ShadowHost())
         return traverseSiblingsForV1HostChild(node, direction);
 
-    if (shadowWhereNodeCanBeDistributed(node))
+    if (shadowWhereNodeCanBeDistributedForV0(node))
         return traverseSiblingsForV0Distribution(node, direction);
 
     if (Node* found = resolveDistributionStartingAt(direction == TraversalDirectionForward ? node.nextSibling() : node.previousSibling(), direction))
         return found;
 
     if (!node.isInV0ShadowTree())
         return nullptr;
 
     // For v0 older shadow tree
     if (node.parentNode() && node.parentNode()->isShadowRoot()) {
@@ skipping 45 matching lines @@
     if (parent && isHTMLSlotElement(parent)) {
         HTMLSlotElement& slot = toHTMLSlotElement(*parent);
         if (!slot.assignedNodes().isEmpty())
             return nullptr;
         return traverseParent(slot, details);
     }
 
     if (canBeDistributedToInsertionPoint(node))
         return traverseParentForV0(node, details);
 
-    DCHECK(!shadowWhereNodeCanBeDistributed(node));
+    DCHECK(!shadowWhereNodeCanBeDistributedForV0(node));
     return traverseParentOrHost(node);
 }
 
 ContainerNode* FlatTreeTraversal::traverseParentForV0(const Node& node, ParentTraversalDetails* details)
 {
-    if (shadowWhereNodeCanBeDistributed(node)) {
+    if (shadowWhereNodeCanBeDistributedForV0(node)) {
         if (const InsertionPoint* insertionPoint = resolveReprojection(&node)) {
             if (details)
                 details->didTraverseInsertionPoint(insertionPoint);
             // The node is distributed. But the distribution was stopped at this insertion point.
-            if (shadowWhereNodeCanBeDistributed(*insertionPoint))
+            if (shadowWhereNodeCanBeDistributedForV0(*insertionPoint))
                 return nullptr;
             return traverseParent(*insertionPoint);
         }
         return nullptr;
     }
     ContainerNode* parent = traverseParentOrHost(node);
     if (isActiveInsertionPoint(*parent))
         return nullptr;
     return parent;
 }
@@ skipping 158 matching lines @@
 Node& FlatTreeTraversal::lastWithinOrSelf(const Node& node)
 {
     assertPrecondition(node);
     Node* lastDescendant = lastWithin(node);
     Node& result = lastDescendant ? *lastDescendant : const_cast<Node&>(node);
     assertPostcondition(&result);
     return result;
 }
 
 } // namespace blink