Clean up ShadowRootRareData, ShadowRoot and SlotAssignment

third_party/WebKit/Source/core/dom/shadow/SlotAssignment.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/dom/shadow/SlotAssignment.h"
 
 #include "core/HTMLNames.h"
 #include "core/dom/ElementTraversal.h"
 #include "core/dom/NodeTraversal.h"
 #include "core/dom/shadow/ElementShadow.h"
 #include "core/dom/shadow/InsertionPoint.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/html/HTMLSlotElement.h"
 
 namespace blink {
 
+
+SlotAssignment::SlotAssignment()
+    : m_descendantSlotCount(0)
+{
+}
+
 HTMLSlotElement* SlotAssignment::assignedSlotFor(const Node& node) const
 {
     return m_assignment.get(const_cast<Node*>(&node));
 }
 
 static void detachNotAssignedNode(Node& node)
 {
     if (node.layoutObject())
         node.lazyReattachIfAttached();
 }
@@ skipping 73 matching lines @@
         slot.appendDistributedNodesFrom(toHTMLSlotElement(hostChild));
     else
         slot.appendDistributedNode(hostChild);
 
     if (slot.isChildOfV1ShadowHost())
         slot.parentElementShadow()->setNeedsDistributionRecalc();
 }
 
 DEFINE_TRACE(SlotAssignment)
 {
+    visitor->trace(m_descendantSlots);
     visitor->trace(m_assignment);
 }
 
 } // namespace blink