Replace style sharing cousin list search with LRU

Source/core/dom/ContainerNode.cpp

Index: Source/core/dom/ContainerNode.cpp
diff --git a/Source/core/dom/ContainerNode.cpp b/Source/core/dom/ContainerNode.cpp
index 1b26b71ed4092b7f264fd8962e5148ff451b7108..77e55031ac4e6e9c071ff02a63b3b886761ab2c8 100644
--- a/Source/core/dom/ContainerNode.cpp
+++ b/Source/core/dom/ContainerNode.cpp
@@ -25,6 +25,7 @@
 
 #include "bindings/v8/ExceptionState.h"
 #include "bindings/v8/ExceptionStatePlaceholder.h"
+#include "core/css/resolver/StyleResolver.h"
 #include "core/dom/ChildListMutationScope.h"
 #include "core/dom/ContainerNodeAlgorithms.h"
 #include "core/dom/EventNames.h"
@@ -1036,6 +1037,8 @@ static void updateTreeAfterInsertion(ContainerNode* parent, Node* child, AttachB
             child->lazyAttach();
         else
             child->attach();
+        if (StyleResolver* resolver = parent->document()->document()->styleResolverIfExists())

[esprehn, 2013/08/20 00:48:01]

document()->document() is nonsense. Why are you going through parent here
instead of just document() on yourself?

[leviw_travelin_and_unemployed, 2013/08/20 00:54:09]

document()->document() is a mistake, but this is a static function. There's no
this to use.

+            resolver->clearStyleSharingList();
     }
 
     dispatchChildInsertionEvents(child);