Revert of Call Element::rebuildLayoutTree from Document::updateStyle directly

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc.
  * All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
@@ skipping 1885 matching lines @@
       if (change != IndependentInherit)
         data->clearComputedStyle();
 
       if (change >= IndependentInherit) {
         if (ElementAnimations* elementAnimations = data->elementAnimations())
           elementAnimations->setAnimationStyleChange(false);
       }
     }
     if (parentComputedStyle())
       change = recalcOwnStyle(change, nextTextSibling);
-    // Needed because the rebuildLayoutTree code needs to see what the
-    // styleChangeType() was on reattach roots. See Node::reattachLayoutTree()
-    // for an example.
-    if (change != Reattach)
-      clearNeedsStyleRecalc();
+    clearNeedsStyleRecalc();
+    clearNeedsReattachLayoutTree();
   }
 
-  // If we are going to reattach we don't need to recalc the style of
-  // our descendants anymore.
-  if (change < Reattach &&
-      (change >= UpdatePseudoElements || childNeedsStyleRecalc())) {
+  // If we reattached we don't need to recalc the style of our descendants
+  // anymore.
+  if ((change >= UpdatePseudoElements && change < Reattach) ||
+      childNeedsStyleRecalc()) {
     SelectorFilterParentScope filterScope(*this);
     StyleSharingDepthScope sharingScope(*this);
 
     updatePseudoElement(PseudoIdBefore, change);
 
     if (change > UpdatePseudoElements || childNeedsStyleRecalc()) {
       for (ShadowRoot* root = youngestShadowRoot(); root;
            root = root->olderShadowRoot()) {
         if (root->shouldCallRecalcStyle(change))
           root->recalcStyle(change);
       }
       recalcDescendantStyles(change);
     }
 
     updatePseudoElement(PseudoIdAfter, change);
     updatePseudoElement(PseudoIdBackdrop, change);
 
     // If our children have changed then we need to force the first-letter
     // checks as we don't know if they effected the first letter or not.
     // This can be seen when a child transitions from floating to
     // non-floating we have to take it into account for the first letter.
     updatePseudoElement(PseudoIdFirstLetter,
                         childNeedsStyleRecalc() ? Force : change);
 
     clearChildNeedsStyleRecalc();
+    clearChildNeedsReattachLayoutTree();
   }
 
   if (hasCustomStyleCallbacks())
     didRecalcStyle();
 }
 
 PassRefPtr<ComputedStyle> Element::propagateInheritedProperties(
     StyleRecalcChange change) {
   if (change != IndependentInherit)
     return nullptr;
@@ skipping 39 matching lines @@
   } else {
     INCREMENT_STYLE_STATS_COUNTER(document().styleEngine(), stylesChanged, 1);
   }
 
   if (localChange == Reattach) {
     StyleReattachData styleReattachData;
     styleReattachData.computedStyle = std::move(newStyle);
     styleReattachData.nextTextSibling = nextTextSibling;
     document().addStyleReattachData(*this, styleReattachData);
     setNeedsReattachLayoutTree();
-    return Reattach;
+    return rebuildLayoutTree();
   }
 
   DCHECK(oldStyle);
 
   if (localChange != NoChange)
     updateCallbackSelectors(oldStyle.get(), newStyle.get());
 
   if (LayoutObject* layoutObject = this->layoutObject()) {
     if (localChange != NoChange ||
         pseudoStyleCacheIsInvalid(oldStyle.get(), newStyle.get())) {
@@ skipping 20 matching lines @@
         return Inherit;
       newStyle->copyChildDependentFlagsFrom(*oldStyle);
     }
     if (oldStyle->hasPseudoElementStyle() || newStyle->hasPseudoElementStyle())
       return UpdatePseudoElements;
   }
 
   return localChange;
 }
 
-void Element::rebuildLayoutTree() {
+StyleRecalcChange Element::rebuildLayoutTree() {
   DCHECK(inActiveDocument());
+  StyleReattachData styleReattachData = document().getStyleReattachData(*this);
+  AttachContext reattachContext;
+  reattachContext.resolvedStyle = styleReattachData.computedStyle.get();
+  bool layoutObjectWillChange = needsAttach() || layoutObject();
+
+  // We are calling Element::rebuildLayoutTree() from inside
+  // Element::recalcOwnStyle where we set the NeedsReattachLayoutTree
+  // flag - so needsReattachLayoutTree() should always be true.
   DCHECK(parentNode());
+  DCHECK(parentNode()->childNeedsReattachLayoutTree());
+  DCHECK(needsReattachLayoutTree());
+  reattachLayoutTree(reattachContext);
+  // Since needsReattachLayoutTree() is always true we go into
+  // reattachLayoutTree() which reattaches all the descendant
+  // sub-trees. At this point no child should need reattaching.
+  DCHECK(!childNeedsReattachLayoutTree());
 
-  if (needsReattachLayoutTree()) {
-    StyleReattachData styleReattachData =
-        document().getStyleReattachData(*this);
-    AttachContext reattachContext;
-    reattachContext.resolvedStyle = styleReattachData.computedStyle.get();
-    bool layoutObjectWillChange =
-        getStyleChangeType() == NeedsReattachStyleChange || layoutObject();
-    reattachLayoutTree(reattachContext);
-    if (layoutObjectWillChange || layoutObject()) {
-      // nextTextSibling is passed on to recalcStyle from recalcDescendantStyles
-      // we can either traverse the current subtree from this node onwards
-      // or store it.
-      // The choice is between increased time and increased memory complexity.
-      reattachWhitespaceSiblingsIfNeeded(styleReattachData.nextTextSibling);
-    }
-  } else if (childNeedsReattachLayoutTree()) {
-    DCHECK(!needsReattachLayoutTree());
-    SelectorFilterParentScope filterScope(*this);
-    StyleSharingDepthScope sharingScope(*this);
-    reattachPseudoElementLayoutTree(PseudoIdBefore);
-    rebuildShadowRootLayoutTree();
-    rebuildChildrenLayoutTrees();
-    reattachPseudoElementLayoutTree(PseudoIdAfter);
-    reattachPseudoElementLayoutTree(PseudoIdBackdrop);
-    reattachPseudoElementLayoutTree(PseudoIdFirstLetter);
+  if (layoutObjectWillChange || layoutObject()) {
+    // nextTextSibling is passed on to recalcStyle from recalcDescendantStyles
+    // we can either traverse the current subtree from this node onwards
+    // or store it.
+    // The choice is between increased time and increased memory complexity.
+    reattachWhitespaceSiblingsIfNeeded(styleReattachData.nextTextSibling);
+    return Reattach;
   }
-  DCHECK(!needsStyleRecalc());
-  DCHECK(!childNeedsStyleRecalc());
-  DCHECK(!needsReattachLayoutTree());
-  DCHECK(!childNeedsReattachLayoutTree());
-}
-
-void Element::rebuildShadowRootLayoutTree() {
-  for (ShadowRoot* root = youngestShadowRoot(); root;
-       root = root->olderShadowRoot()) {
-    if (root->needsReattachLayoutTree() || root->childNeedsReattachLayoutTree())
-      root->rebuildLayoutTree();
-  }
-}
-
-void Element::reattachPseudoElementLayoutTree(PseudoId pseudoId) {
-  if (PseudoElement* element = pseudoElement(pseudoId)) {
-    if (element->needsReattachLayoutTree() ||
-        element->childNeedsReattachLayoutTree())
-      element->rebuildLayoutTree();
-  } else {
-    createPseudoElementIfNeeded(pseudoId);
-  }
+  return ReattachNoLayoutObject;
 }
 
 void Element::updateCallbackSelectors(const ComputedStyle* oldStyle,
                                       const ComputedStyle* newStyle) {
   Vector<String> emptyVector;
   const Vector<String>& oldCallbackSelectors =
       oldStyle ? oldStyle->callbackSelectors() : emptyVector;
   const Vector<String>& newCallbackSelectors =
       newStyle ? newStyle->callbackSelectors() : emptyVector;
   if (oldCallbackSelectors.isEmpty() && newCallbackSelectors.isEmpty())
@@ skipping 2064 matching lines @@
 }
 
 DEFINE_TRACE_WRAPPERS(Element) {
   if (hasRareData()) {
     visitor->traceWrappers(elementRareData());
   }
   ContainerNode::traceWrappers(visitor);
 }
 
 }  // namespace blink