Rewrite Shadow DOM distribution engine to support partial synchronous distribution for v1

third_party/WebKit/Source/core/dom/shadow/ShadowRoot.h

Index: third_party/WebKit/Source/core/dom/shadow/ShadowRoot.h
diff --git a/third_party/WebKit/Source/core/dom/shadow/ShadowRoot.h b/third_party/WebKit/Source/core/dom/shadow/ShadowRoot.h
index 271865f311bba10431b478cf8d47c209dc42133f..f63f3607c3614ffe45bfa3e759337e69cee5650e 100644
--- a/third_party/WebKit/Source/core/dom/shadow/ShadowRoot.h
+++ b/third_party/WebKit/Source/core/dom/shadow/ShadowRoot.h
@@ -116,15 +116,8 @@ public:
 
     SlotAssignment& ensureSlotAssignment();
 
-    void didAddSlot();
-    void didRemoveSlot();
-    const HeapVector<Member<HTMLSlotElement>>& descendantSlots();
-
-    void assignV1();
     void distributeV1();
 
-    HTMLSlotElement* assignedSlotFor(const Node&) const;
-
     Element* activeElement() const;
 
     String innerHTML() const;
@@ -162,19 +155,15 @@ private:
     // FIXME: This shouldn't happen. https://bugs.webkit.org/show_bug.cgi?id=88834
     bool isOrphan() const { return !host(); }
 
-    void invalidateDescendantSlots();
-    unsigned descendantSlotCount() const;
-
     Member<ShadowRootRareDataV0> m_shadowRootRareDataV0;
     Member<StyleSheetList> m_styleSheetList;
     Member<SlotAssignment> m_slotAssignment;
-    unsigned m_numberOfStyles : 13;
+    unsigned m_numberOfStyles : 14;
     unsigned m_childShadowRootCount : 13;
     unsigned m_type : 2;
     unsigned m_registeredWithParentShadowRoot : 1;
     unsigned m_descendantInsertionPointsIsValid : 1;
     unsigned m_delegatesFocus : 1;
-    unsigned m_descendantSlotsIsValid : 1;
 };
 
 inline Element* ShadowRoot::activeElement() const