Revert "Replace style sharing cousin list search with LRU"

Source/core/css/resolver/StyleResolver.h

Index: Source/core/css/resolver/StyleResolver.h
diff --git a/Source/core/css/resolver/StyleResolver.h b/Source/core/css/resolver/StyleResolver.h
index 15db7d44f56cfc4e4fb8d85738ac5cb552dd7075..a8fd43f40c2630c7eb011e2125b822899d6b30c0 100644
--- a/Source/core/css/resolver/StyleResolver.h
+++ b/Source/core/css/resolver/StyleResolver.h
@@ -36,7 +36,6 @@
 #include "core/css/resolver/StyleBuilder.h"
 #include "core/css/resolver/StyleResolverState.h"
 #include "core/css/resolver/StyleResourceLoader.h"
-#include "wtf/Deque.h"
 #include "wtf/HashMap.h"
 #include "wtf/HashSet.h"
 #include "wtf/RefPtr.h"
@@ -86,9 +85,6 @@ enum RuleMatchingBehavior {
     MatchOnlyUserAgentRules,
 };
 
-const unsigned styleSharingListSize = 20;
-typedef WTF::Deque<Element*, styleSharingListSize> StyleSharingList;
-
 #undef STYLE_STATS
 
 #ifdef STYLE_STATS
@@ -279,11 +275,6 @@ public:
 
     const RuleFeatureSet& ruleFeatureSet() const { return m_features; }
 
-    StyleSharingList& styleSharingList() { return m_styleSharingList; }
-
-    void addToStyleSharingList(Element*);
-    void clearStyleSharingList();
-
 #ifdef STYLE_STATS
     ALWAYS_INLINE static StyleSharingStats& styleSharingStats() { return m_styleSharingStats; }
 #endif
@@ -367,8 +358,6 @@ private:
 
     StyleResourceLoader m_styleResourceLoader;
 
-    StyleSharingList m_styleSharingList;
-
 #ifdef STYLE_STATS
     static StyleSharingStats m_styleSharingStats;
 #endif