Support the essential part of Shadow DOM v1

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

Index: third_party/WebKit/Source/core/dom/shadow/ElementShadow.h
diff --git a/third_party/WebKit/Source/core/dom/shadow/ElementShadow.h b/third_party/WebKit/Source/core/dom/shadow/ElementShadow.h
index ea06f7786de792acfe1a44ddf5d0918c224697e7..bd67343226c0eea6d9d0c7e1dd60c6bc74069c69 100644
--- a/third_party/WebKit/Source/core/dom/shadow/ElementShadow.h
+++ b/third_party/WebKit/Source/core/dom/shadow/ElementShadow.h
@@ -31,6 +31,7 @@
 #include "core/dom/shadow/InsertionPoint.h"
 #include "core/dom/shadow/SelectRuleFeatureSet.h"
 #include "core/dom/shadow/ShadowRoot.h"
+#include "core/dom/shadow/SlotAssignment.h"
 #include "platform/heap/Handle.h"
 #include "wtf/DoublyLinkedList.h"
 #include "wtf/HashMap.h"
@@ -51,6 +52,19 @@ public:
     ShadowRoot* oldestShadowRoot() const { return m_shadowRoots.tail(); }
     ElementShadow* containingShadow() const;
 
+    ShadowRoot* shadowRootIfV1() const
+    {
+        if (isV1())
+            return &youngestShadowRoot();
+        return nullptr;
+    }
+
+    HTMLSlotElement* assignedSlotFor(const Node& node) const
+    {
+        ASSERT(m_slotAssignment);
+        return m_slotAssignment->assignedSlotFor(node);
+    }
+
     ShadowRoot& addShadowRoot(Element& shadowHost, ShadowRootType);
 
     bool hasSameStyles(const ElementShadow*) const;
@@ -69,6 +83,8 @@ public:
 
     void didDistributeNode(const Node*, InsertionPoint*);
 
+    bool isV1() const { return youngestShadowRoot().isV1(); };
+
     DECLARE_TRACE();
 
 private:
@@ -90,8 +106,6 @@ private:
     bool needsSelectFeatureSet() const { return m_needsSelectFeatureSet; }
     void setNeedsSelectFeatureSet() { m_needsSelectFeatureSet = true; }
 
-    bool isV1() const { return youngestShadowRoot().type() == ShadowRootType::Open || youngestShadowRoot().type() == ShadowRootType::Closed; };
-
 #if ENABLE(OILPAN)
     // The cost of |new| in Oilpan is lower than non-Oilpan.  We should reduce
     // the size of HashMap entry.
@@ -106,6 +120,9 @@ private:
     DoublyLinkedList<ShadowRoot> m_shadowRoots;
     bool m_needsDistributionRecalc;
     bool m_needsSelectFeatureSet;
+
+    // TODO(hayato): ShadowRoot should be an owner of SlotAssigment
+    OwnPtr<SlotAssignment> m_slotAssignment;
 };
 
 inline Element* ElementShadow::host() const
@@ -128,6 +145,13 @@ inline ShadowRoot* Element::youngestShadowRoot() const
     return 0;
 }
 
+inline ShadowRoot* Element::shadowRootIfV1() const
+{
+    if (ElementShadow* shadow = this->shadow())
+        return shadow->shadowRootIfV1();
+    return nullptr;
+}
+
 inline ElementShadow* ElementShadow::containingShadow() const
 {
     if (ShadowRoot* parentRoot = host()->containingShadowRoot())