Clean up ShadowRootRareData, ShadowRoot and SlotAssignment

third_party/WebKit/Source/core/dom/DocumentOrShadowRoot.h

Index: third_party/WebKit/Source/core/dom/DocumentOrShadowRoot.h
diff --git a/third_party/WebKit/Source/core/dom/DocumentOrShadowRoot.h b/third_party/WebKit/Source/core/dom/DocumentOrShadowRoot.h
index 1f4a04bd419348cfc3d0f636dc3c328e91ddde11..11fbf32b7b9da7d7754da24cd0ee2058703e0a52 100644
--- a/third_party/WebKit/Source/core/dom/DocumentOrShadowRoot.h
+++ b/third_party/WebKit/Source/core/dom/DocumentOrShadowRoot.h
@@ -24,12 +24,12 @@ public:
 
     static StyleSheetList* styleSheets(Document& document)
     {
-        return document.styleSheets();
+        return &document.styleSheets();
     }
 
     static StyleSheetList* styleSheets(ShadowRoot& shadowRoot)
     {
-        return shadowRoot.styleSheets();
+        return &shadowRoot.styleSheets();
     }
 
     static DOMSelection* getSelection(TreeScope& treeScope)