Schedule sibling invalidation sets for sibling insert/remove.

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

Index: third_party/WebKit/Source/core/dom/StyleEngine.cpp
diff --git a/third_party/WebKit/Source/core/dom/StyleEngine.cpp b/third_party/WebKit/Source/core/dom/StyleEngine.cpp
index b7cccd69a0808c85471a3698915ce9c4f613368e..6a0b92239da42b36fdf75464c5f48252344e4d82 100644
--- a/third_party/WebKit/Source/core/dom/StyleEngine.cpp
+++ b/third_party/WebKit/Source/core/dom/StyleEngine.cpp
@@ -37,6 +37,7 @@
 #include "core/css/resolver/ScopedStyleResolver.h"
 #include "core/dom/DocumentStyleSheetCollector.h"
 #include "core/dom/Element.h"
+#include "core/dom/ElementTraversal.h"
 #include "core/dom/ProcessingInstruction.h"
 #include "core/dom/ShadowTreeStyleSheetCollection.h"
 #include "core/dom/StyleChangeReason.h"
@@ -690,6 +691,56 @@ void StyleEngine::pseudoStateChangedForElement(CSSSelector::PseudoType pseudoTyp
     m_styleInvalidator.scheduleInvalidationSetsForElement(invalidationLists, element);
 }
 
+void StyleEngine::scheduleSiblingInvalidationsForElement(Element& element, Element& schedulingElement, unsigned minDirectAdjacent, bool invalidateSchedulingElement)
+{
+    InvalidationLists invalidationLists;
+
+    RuleFeatureSet& ruleFeatureSet = ensureResolver().ensureUpdatedRuleFeatureSet();
+
+    if (element.hasID())
+        ruleFeatureSet.collectSiblingInvalidationSetForId(invalidationLists, element, element.idForStyleResolution(), minDirectAdjacent);
+
+    if (element.hasClass()) {
+        const SpaceSplitString& classNames = element.classNames();
+        for (size_t i = 0; i < classNames.size(); i++)
+            ruleFeatureSet.collectSiblingInvalidationSetForClass(invalidationLists, element, classNames[i], minDirectAdjacent);
+    }
+
+    for (const Attribute& attribute : element.attributes())
+        ruleFeatureSet.collectSiblingInvalidationSetForAttribute(invalidationLists, element, attribute.name(), minDirectAdjacent);
+
+    ruleFeatureSet.collectUniversalSiblingInvalidationSet(invalidationLists, minDirectAdjacent);
+
+    m_styleInvalidator.scheduleInvalidationSetsForElement(invalidationLists, schedulingElement);
+    if (invalidateSchedulingElement)
+        m_styleInvalidator.scheduleDescendantsFromSiblingSets(schedulingElement, invalidationLists.siblings);
+}
+
+void StyleEngine::scheduleInvalidationsForInsertedSibling(Element* beforeElement, Element& insertedElement)
+{
+    unsigned affectedSiblings = insertedElement.parentNode()->childrenAffectedByIndirectAdjacentRules() ? UINT_MAX : m_maxDirectAdjacentSelectors;
+
+    scheduleSiblingInvalidationsForElement(insertedElement, insertedElement, 1, false);
+
+    Element* schedulingElement = &insertedElement;
+    for (unsigned i = 1; beforeElement && i <= affectedSiblings; i++, beforeElement = ElementTraversal::previousSibling(*(schedulingElement = beforeElement)))
+        scheduleSiblingInvalidationsForElement(*beforeElement, *schedulingElement, i, false);
+}
+
+void StyleEngine::scheduleInvalidationsForRemovedSibling(Element* beforeElement, Element& removedElement, Element& afterElement)
+{
+    unsigned affectedSiblings = afterElement.parentNode()->childrenAffectedByIndirectAdjacentRules() ? UINT_MAX : m_maxDirectAdjacentSelectors;
+
+    Element* schedulingElement = beforeElement;
+    if (!schedulingElement)
+        schedulingElement = &afterElement;
+
+    scheduleSiblingInvalidationsForElement(removedElement, *schedulingElement, 1, schedulingElement == &afterElement);
+
+    for (unsigned i = 2; beforeElement && i <= affectedSiblings; i++, beforeElement = ElementTraversal::previousSibling(*beforeElement))
+        scheduleSiblingInvalidationsForElement(*beforeElement, *beforeElement, i, false);
+}
+
 void StyleEngine::setStatsEnabled(bool enabled)
 {
     if (!enabled) {
@@ -702,6 +753,24 @@ void StyleEngine::setStatsEnabled(bool enabled)
         m_styleResolverStats->reset();
 }
 
+void StyleEngine::willRemoveChild(Node& child)
+{
+    if (!child.needsStyleInvalidation())
+        return;
+    if (!child.isElementNode())
+        return;
+    if (!child.inShadowIncludingDocument())
+        return;
+
+    Element* elementTo = ElementTraversal::previousSibling(child);
+    bool invalidateElementTo = !elementTo;
+    if (!elementTo)
+        elementTo = ElementTraversal::nextSibling(child);
+    if (!elementTo)
+        return;
+    styleInvalidator().rescheduleSiblingInvalidationSetsForRemovedElement(toElement(child), *elementTo, invalidateElementTo);
+}
+
 void StyleEngine::setPreferredStylesheetSetNameIfNotSet(const String& name)
 {
     if (!m_preferredStylesheetSetName.isEmpty())