Remove needsShadowTreeWalker flag

Source/core/dom/NodeRenderingTraversal.h

Index: Source/core/dom/NodeRenderingTraversal.h
diff --git a/Source/core/dom/NodeRenderingTraversal.h b/Source/core/dom/NodeRenderingTraversal.h
index 23bee1db1b15f177235b8240178681967a1574ae..13fb985a4edafdaed109bf01be68712e7500c717 100644
--- a/Source/core/dom/NodeRenderingTraversal.h
+++ b/Source/core/dom/NodeRenderingTraversal.h
@@ -66,11 +66,8 @@ private:
 
 ContainerNode* parent(const Node*);
 ContainerNode* parent(const Node*, ParentDetails*);
-ContainerNode* parentSlow(const Node*, ParentDetails*);
 Node* nextSibling(const Node*);
-Node* nextSiblingSlow(const Node*);
 Node* previousSibling(const Node*);
-Node* previousSiblingSlow(const Node*);
 
 Node* nextInScope(const Node*);
 Node* previousInScope(const Node*);
@@ -83,46 +80,6 @@ inline ContainerNode* parent(const Node* node)
     return parent(node, &unusedDetails);
 }
 
-inline ContainerNode* parent(const Node* node, ParentDetails* details)
-{
-    if (!node->needsShadowTreeWalker()) {
-#ifndef NDEBUG
-        ParentDetails slowDetails;
-        ASSERT(node->parentNode() == parentSlow(node, &slowDetails));
-        ASSERT(slowDetails == *details);
-#endif
-        return node->parentNodeGuaranteedHostFree();
-    }
-
-    return parentSlow(node, details);
-}
-
-inline Node* nextSibling(const Node* node)
-{
-    if (!node->needsShadowTreeWalker()) {
-        Node* next = node->nextSibling();
-        if (!next || !next->isInsertionPoint()) {
-            ASSERT(nextSiblingSlow(node) == next);
-            return next;
-        }
-    }
-
-    return nextSiblingSlow(node);
-}
-
-inline Node* previousSibling(const Node* node)
-{
-    if (!node->needsShadowTreeWalker()) {
-        Node* prev = node->previousSibling();
-        if (!prev || !prev->isInsertionPoint()) {
-            ASSERT(previousSiblingSlow(node) == prev);
-            return prev;
-        }
-    }
-
-    return previousSiblingSlow(node);
-}
-
 }
 
 } // namespace WebCore