Persist invalidation sets on detach root

third_party/WebKit/Source/core/css/invalidation/StyleInvalidator.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 
 #include "core/css/invalidation/StyleInvalidator.h"
 
 #include "core/css/invalidation/InvalidationSet.h"
 #include "core/dom/Document.h"
@@ skipping 25 matching lines @@
     if (Element* documentElement = document.documentElement())
         invalidate(*documentElement, recursionData, siblingData);
     document.clearChildNeedsStyleInvalidation();
     document.clearNeedsStyleInvalidation();
     m_pendingInvalidationMap.clear();
 }
 
 void StyleInvalidator::scheduleInvalidationSetsForElement(const InvalidationLists& invalidationLists, Element& element)
 {
     ASSERT(element.inActiveDocument());
-    if (element.styleChangeType() >= SubtreeStyleChange)
-        return;
-
     bool requiresDescendantInvalidation = false;
 
-    for (auto& invalidationSet : invalidationLists.descendants) {
-        if (invalidationSet->wholeSubtreeInvalid()) {
-            element.setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::StyleInvalidator));
-            clearInvalidation(element);
-            return;
+    if (element.styleChangeType() < SubtreeStyleChange) {
+        for (auto& invalidationSet : invalidationLists.descendants) {
+            if (invalidationSet->wholeSubtreeInvalid()) {
+                element.setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::StyleInvalidator));
+                requiresDescendantInvalidation = false;
+                break;
+            }
+
+            if (invalidationSet->invalidatesSelf())
+                element.setNeedsStyleRecalc(LocalStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::StyleInvalidator));
+
+            if (!invalidationSet->isEmpty())
+                requiresDescendantInvalidation = true;
         }
-
-        if (invalidationSet->invalidatesSelf())
-            element.setNeedsStyleRecalc(LocalStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::StyleInvalidator));
-
-        if (!invalidationSet->isEmpty())
-            requiresDescendantInvalidation = true;
     }
 
     if (!requiresDescendantInvalidation && (invalidationLists.siblings.isEmpty() || !element.nextSibling()))
         return;
 
     element.setNeedsStyleInvalidation();
 
     PendingInvalidations& pendingInvalidations = ensurePendingInvalidations(element);
     if (element.nextSibling()) {
         for (auto& invalidationSet : invalidationLists.siblings)
@@ skipping 219 matching lines @@
 }
 
 DEFINE_TRACE(StyleInvalidator)
 {
 #if ENABLE(OILPAN)
     visitor->trace(m_pendingInvalidationMap);
 #endif
 }
 
 } // namespace blink