List marker pseudo elements.

Source/core/dom/ElementRareData.h

Index: Source/core/dom/ElementRareData.h
diff --git a/Source/core/dom/ElementRareData.h b/Source/core/dom/ElementRareData.h
index 4061eb380325e2822bcd7980dc6daea120c05f26..3340bdd98fdd338250f57aa199ff91e5ad81fec9 100644
--- a/Source/core/dom/ElementRareData.h
+++ b/Source/core/dom/ElementRareData.h
@@ -146,6 +146,7 @@ private:
     RefPtr<RenderStyle> m_computedStyle;
     RefPtrWillBeMember<CustomElementDefinition> m_customElementDefinition;
 
+    RefPtrWillBeMember<PseudoElement> m_marker;
     RefPtrWillBeMember<PseudoElement> m_generatedBefore;
     RefPtrWillBeMember<PseudoElement> m_generatedAfter;
     RefPtrWillBeMember<PseudoElement> m_generatedFirstLetter;
@@ -172,6 +173,7 @@ inline ElementRareData::~ElementRareData()
 #if !ENABLE(OILPAN)
     ASSERT(!m_shadow);
 #endif
+    ASSERT(!m_marker);
     ASSERT(!m_generatedBefore);
     ASSERT(!m_generatedAfter);
     ASSERT(!m_generatedFirstLetter);
@@ -180,7 +182,7 @@ inline ElementRareData::~ElementRareData()
 
 inline bool ElementRareData::hasPseudoElements() const
 {
-    return m_generatedBefore || m_generatedAfter || m_backdrop || m_generatedFirstLetter;
+    return m_generatedBefore || m_generatedAfter || m_backdrop || m_generatedFirstLetter || m_marker;
 }
 
 inline void ElementRareData::clearPseudoElements()
@@ -188,12 +190,18 @@ inline void ElementRareData::clearPseudoElements()
     setPseudoElement(BEFORE, nullptr);
     setPseudoElement(AFTER, nullptr);
     setPseudoElement(BACKDROP, nullptr);
+    setPseudoElement(MARKER, nullptr);
     setPseudoElement(FIRST_LETTER, nullptr);
 }
 
 inline void ElementRareData::setPseudoElement(PseudoId pseudoId, PassRefPtrWillBeRawPtr<PseudoElement> element)
 {
     switch (pseudoId) {
+    case MARKER:
+        if (m_marker)
+            m_marker->dispose();
+        m_marker = element;
+        break;
     case BEFORE:
         if (m_generatedBefore)
             m_generatedBefore->dispose();
@@ -222,6 +230,8 @@ inline void ElementRareData::setPseudoElement(PseudoId pseudoId, PassRefPtrWillB
 inline PseudoElement* ElementRareData::pseudoElement(PseudoId pseudoId) const
 {
     switch (pseudoId) {
+    case MARKER:
+        return m_marker.get();
     case BEFORE:
         return m_generatedBefore.get();
     case AFTER: