Call Element::rebuildLayoutTree from Document::updateStyle directly

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All
  * rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
@@ skipping 1350 matching lines @@
 
     return documentElement();
   }
 
   return body();
 }
 
 // We use HashMap::set over HashMap::add here as we want to
 // replace the ComputedStyle but not the Element if the Element is
 // already present.
-void Document::addStyleReattachData(Element& element,
+void Document::addStyleReattachData(Node& node,
                                     StyleReattachData& styleReattachData) {
-  m_styleReattachDataMap.set(&element, styleReattachData);
+  m_styleReattachDataMap.set(&node, styleReattachData);
 }
 
-StyleReattachData Document::getStyleReattachData(Element& element) {
-  return m_styleReattachDataMap.get(&element);
+StyleReattachData Document::getStyleReattachData(Node& node) {
+  return m_styleReattachDataMap.get(&node);
 }
 
 /*
  * Performs three operations:
  *  1. Convert control characters to spaces
  *  2. Trim leading and trailing spaces
  *  3. Collapse internal whitespace.
  */
 template <typename CharacterType>
 static inline String canonicalizedTitle(Document* document,
@@ skipping 405 matching lines @@
 
   // Resolved rem units are stored in the matched properties cache so we need to
   // make sure to invalidate the cache if the documentElement needed to reattach
   // or the font size changed and then trigger a full document recalc. We also
   // need to clear it here since the call to styleForElement on the body above
   // can cache bad values for rem units if the documentElement's style was
   // dirty. We could keep track of which elements depend on rem units like we do
   // for viewport styles, but we assume root font size changes are rare and just
   // invalidate the cache for now.
   if (styleEngine().usesRemUnits() &&
-      (documentElement()->needsAttach() ||
+      (documentElement()->needsReattachLayoutTree() ||
        !documentElement()->computedStyle() ||
        documentElement()->computedStyle()->fontSize() !=
            documentElementStyle->fontSize())) {
     ensureStyleResolver().invalidateMatchedPropertiesCache();
     documentElement()->setNeedsStyleRecalc(
         SubtreeStyleChange,
         StyleChangeReasonForTracing::create(StyleChangeReason::FontSizeChange));
   }
 
   EOverflowAnchor overflowAnchor = AnchorAuto;
@@ skipping 230 matching lines @@
   StyleResolver& resolver = ensureStyleResolver();
 
   bool shouldRecordStats;
   TRACE_EVENT_CATEGORY_GROUP_ENABLED("blink,blink_style", &shouldRecordStats);
   styleEngine().setStatsEnabled(shouldRecordStats);
 
   if (Element* documentElement = this->documentElement()) {
     inheritHtmlAndBodyElementStyles(change);
     if (documentElement->shouldCallRecalcStyle(change))
       documentElement->recalcStyle(change);
+    DCHECK(!documentElement->needsStyleRecalc());
+    DCHECK(!documentElement->childNeedsStyleRecalc());
+    if (documentElement->needsReattachLayoutTree() ||
+        documentElement->childNeedsReattachLayoutTree())
+      documentElement->rebuildLayoutTree();
   }
 
   view()->recalcOverflowAfterStyleChange();
 
   // Only retain the HashMap for the duration of StyleRecalc and
   // LayoutTreeConstruction.
   m_styleReattachDataMap.clear();
   clearChildNeedsStyleRecalc();
   clearChildNeedsReattachLayoutTree();
 
@@ skipping 297 matching lines @@
   DCHECK_EQ(m_lifecycle.state(), DocumentLifecycle::Inactive);
   DCHECK(!m_axObjectCache || this != &axObjectCacheOwner());
 
   m_layoutView = new LayoutView(this);
   setLayoutObject(m_layoutView);
 
   m_layoutView->setIsInWindow(true);
   m_layoutView->setStyle(StyleResolver::styleForDocument(*this));
   m_layoutView->compositor()->setNeedsCompositingUpdate(
       CompositingUpdateAfterCompositingInputChange);
+  setNeedsReattachLayoutTree();

[nainar, 2016/11/29 06:13:39]

This is as ContainerNode::attachLayoutTree() asserts that this flag is set. 

+  ContainerNode::attachLayoutTree();
 
-  ContainerNode::attachLayoutTree();
+  DCHECK(!needsReattachLayoutTree());
 
   // The TextAutosizer can't update layout view info while the Document is
   // detached, so update now in case anything changed.
   if (TextAutosizer* autosizer = textAutosizer())
     autosizer->updatePageInfo();
 
   m_frame->documentAttached();
   m_lifecycle.advanceTo(DocumentLifecycle::StyleClean);
 
   if (view())
@@ skipping 4163 matching lines @@
 }
 
 void showLiveDocumentInstances() {
   WeakDocumentSet& set = liveDocumentSet();
   fprintf(stderr, "There are %u documents currently alive:\n", set.size());
   for (Document* document : set)
     fprintf(stderr, "- Document %p URL: %s\n", document,
             document->url().getString().utf8().data());
 }
 #endif