Sibling invalidation sets

Source/core/css/invalidation/InvalidationListData.cpp

Index: Source/core/css/invalidation/InvalidationListData.cpp
diff --git a/Source/platform/exported/WebProcessMemoryDump.cpp b/Source/core/css/invalidation/InvalidationListData.cpp
similarity index 52%
copy from Source/platform/exported/WebProcessMemoryDump.cpp
copy to Source/core/css/invalidation/InvalidationListData.cpp
index f50221da516e9c65810b77c546af813d2cf1efb6..c47a769f6aed296e1b86d4ea5fa39dcea4c87ce5 100644
--- a/Source/platform/exported/WebProcessMemoryDump.cpp
+++ b/Source/core/css/invalidation/InvalidationListData.cpp
@@ -3,12 +3,14 @@
 // found in the LICENSE file.
 
 #include "config.h"
-#include "public/platform/WebProcessMemoryDump.h"
+#include "core/css/invalidation/InvalidationListData.h"
 
 namespace blink {
 
-WebProcessMemoryDump::~WebProcessMemoryDump()
+DEFINE_TRACE(InvalidationListData)
 {
+    visitor->trace(m_invalidationList[InvalidateDescendants]);
+    visitor->trace(m_invalidationList[InvalidateSiblings]);
 }
 
 } // namespace blink