Make all setNeedsReattachLayoutTree happen from updateStyle.

third_party/WebKit/Source/core/dom/Node.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All
  * rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  *
@@ skipping 707 matching lines @@
   document().scheduleLayoutTreeUpdateIfNeeded();
 }
 
 void Node::markAncestorsWithChildNeedsReattachLayoutTree() {
   for (ContainerNode* p = parentOrShadowHostNode();
        p && !p->childNeedsReattachLayoutTree(); p = p->parentOrShadowHostNode())
     p->setChildNeedsReattachLayoutTree();
 }
 
 void Node::setNeedsReattachLayoutTree() {
+  DCHECK(document().inStyleRecalc() &&

[esprehn, 2017/03/21 20:59:56]

Can we use two DCHECKs so it's clear which side failed?

[rune, 2017/03/21 22:25:15]

Done.

+         !document().childNeedsDistributionRecalc());
   setFlag(NeedsReattachLayoutTree);
   markAncestorsWithChildNeedsReattachLayoutTree();
 }
 
 void Node::setNeedsStyleRecalc(StyleChangeType changeType,
                                const StyleChangeReasonForTracing& reason) {
   DCHECK(changeType != NoStyleChange);
   if (!inActiveDocument())
     return;
 
@@ skipping 187 matching lines @@
 }
 
 void Node::detachLayoutTree(const AttachContext& context) {
   DCHECK(document().lifecycle().stateAllowsDetach());
   DocumentLifecycle::DetachScope willDetach(document().lifecycle());
 
   if (layoutObject())
     layoutObject()->destroyAndCleanupAnonymousWrappers();
   setLayoutObject(nullptr);
   setStyleChange(NeedsReattachStyleChange);
-  setFlag(NeedsReattachLayoutTree);
   clearChildNeedsStyleInvalidation();
 }
 
 void Node::reattachWhitespaceSiblingsIfNeeded(Text* start) {
   ScriptForbiddenScope forbidScriptDuringRawIteration;
   for (Node* sibling = start; sibling; sibling = sibling->nextSibling()) {
     if (sibling->isTextNode() && toText(sibling)->containsOnlyWhitespace()) {
       bool hadLayoutObject = !!sibling->layoutObject();
       toText(sibling)->reattachLayoutTreeIfNeeded();
       // If sibling's layout object status didn't change we don't need to
@@ skipping 1589 matching lines @@
   if (node) {
     std::stringstream stream;
     node->printNodePathTo(stream);
     LOG(INFO) << stream.str();
   } else {
     LOG(INFO) << "Cannot showNodePath for <null>";
   }
 }
 
 #endif