Call Element::rebuildLayoutTree from Document::updateStyle directly

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

Index: third_party/WebKit/Source/core/dom/ContainerNode.cpp
diff --git a/third_party/WebKit/Source/core/dom/ContainerNode.cpp b/third_party/WebKit/Source/core/dom/ContainerNode.cpp
index a2ce787cc8e9cc6fcfb7bfad0ca1587b978746c2..f4191e44619a924dd61b532c45cb5450b9999b8a 100644
--- a/third_party/WebKit/Source/core/dom/ContainerNode.cpp
+++ b/third_party/WebKit/Source/core/dom/ContainerNode.cpp
@@ -779,7 +779,6 @@ void ContainerNode::detachLayoutTree(const AttachContext& context) {
   for (Node* child = firstChild(); child; child = child->nextSibling())
     child->detachLayoutTree(childrenContext);
 
-  setChildNeedsStyleRecalc();
   Node::detachLayoutTree(context);
 }
 
@@ -1294,6 +1293,24 @@ void ContainerNode::recalcDescendantStyles(StyleRecalcChange change) {
         lastTextNode = nullptr;
     }
   }
+  clearChildNeedsStyleRecalc();
+}
+
+void ContainerNode::rebuildDescendantLayoutTree() {
+  DCHECK(!needsStyleRecalc());
+  DCHECK(!childNeedsStyleRecalc());
+  DCHECK(!needsReattachLayoutTree());
+
+  for (Node* child = firstChild(); child; child = child->nextSibling()) {
+    if (child->needsReattachLayoutTree() ||
+        child->childNeedsReattachLayoutTree()) {
+      if (child->isTextNode())
+        toText(child)->rebuildTextLayoutTree();
+      else if (child->isElementNode())
+        toElement(child)->rebuildLayoutTree();
+    }
+  }
+  clearChildNeedsReattachLayoutTree();
 }
 
 void ContainerNode::checkForSiblingStyleChanges(SiblingCheckType changeType,