[LayoutNG] PODify NGLayoutInputNode and sub-classes.

third_party/WebKit/Source/core/layout/ng/ng_layout_result.h

Index: third_party/WebKit/Source/core/layout/ng/ng_layout_result.h
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_layout_result.h b/third_party/WebKit/Source/core/layout/ng/ng_layout_result.h
index 77d7be6af16b30642707cfb83633af1a30379929..5604d22156c38c4f607758cec0d56c1412bc730a 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_layout_result.h
+++ b/third_party/WebKit/Source/core/layout/ng/ng_layout_result.h
@@ -32,8 +32,7 @@ class CORE_EXPORT NGLayoutResult : public RefCounted<NGLayoutResult> {
     return physical_fragment_;
   }
 
-  const HeapLinkedHashSet<WeakMember<NGBlockNode>>& OutOfFlowDescendants()
-      const {
+  const Vector<NGBlockNode>& OutOfFlowDescendants() const {
     return out_of_flow_descendants_;
   }
 
@@ -57,13 +56,12 @@ class CORE_EXPORT NGLayoutResult : public RefCounted<NGLayoutResult> {
   friend class NGFragmentBuilder;
 
   NGLayoutResult(PassRefPtr<NGPhysicalFragment> physical_fragment,
-                 PersistentHeapLinkedHashSet<WeakMember<NGBlockNode>>&
-                     out_of_flow_descendants,
+                 Vector<NGBlockNode>& out_of_flow_descendants,
                  Vector<NGStaticPosition> out_of_flow_positions,
                  Vector<RefPtr<NGUnpositionedFloat>>& unpositioned_floats);
 
   RefPtr<NGPhysicalFragment> physical_fragment_;
-  PersistentHeapLinkedHashSet<WeakMember<NGBlockNode>> out_of_flow_descendants_;
+  Vector<NGBlockNode> out_of_flow_descendants_;
   Vector<NGStaticPosition> out_of_flow_positions_;
   Vector<RefPtr<NGUnpositionedFloat>> unpositioned_floats_;
 };