Remove needsShadowTreeWalker flag

Source/core/dom/shadow/ElementShadow.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 23 matching lines @@
 ShadowRoot* ElementShadow::addShadowRoot(Element* shadowHost, ShadowRoot::ShadowRootType type)
 {
     RefPtr<ShadowRoot> shadowRoot = ShadowRoot::create(shadowHost->document(), type);
 
     shadowRoot->setParentOrShadowHostNode(shadowHost);
     shadowRoot->setParentTreeScope(shadowHost->treeScope());
     m_shadowRoots.push(shadowRoot.get());
     m_distributor.didShadowBoundaryChange(shadowHost);
     ChildNodeInsertionNotifier(shadowHost).notify(shadowRoot.get());
 
-    // Existence of shadow roots requires the host and its children to do traversal using ComposedShadowTreeWalker.
-    shadowHost->setNeedsShadowTreeWalker();
-
-    // FIXME(94905): ShadowHost should be reattached during recalcStyle.
-    // Set some flag here and recreate shadow hosts' renderer in
-    // Element::recalcStyle.
     if (shadowHost->attached())
         shadowHost->lazyReattach();
 
     InspectorInstrumentation::didPushShadowRoot(shadowHost, shadowRoot.get());
 
     return shadowRoot.get();
 }
 
 void ElementShadow::removeAllShadowRoots()
 {
@@ skipping 76 matching lines @@
     info.addMember(m_shadowRoots, "shadowRoots");
     ShadowRoot* shadowRoot = m_shadowRoots.head();
     while (shadowRoot) {
         info.addMember(shadowRoot, "shadowRoot");
         shadowRoot = shadowRoot->next();
     }
     info.addMember(m_distributor, "distributor");
 }
 
 } // namespace