[LayoutNG] Stack allocate NGLayoutOpportunityIterator.

third_party/WebKit/Source/core/layout/ng/ng_layout_opportunity_iterator.cc

 // Copyright 2016 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/layout/ng/ng_layout_opportunity_iterator.h"
 
 #include "core/layout/ng/ng_units.h"
 #include "wtf/NonCopyingSort.h"
 
 namespace blink {
@@ skipping 227 matching lines @@
     : constraint_space_(space) {
   // TODO(chrome-layout-team): Combine exclusions that shadow each other.
   auto& exclusions = constraint_space_->Exclusions();
   DCHECK(std::is_sorted(exclusions->storage.begin(), exclusions->storage.end(),
                         &CompareNGExclusionsByTopAsc))
       << "Exclusions are expected to be sorted by TOP";
 
   NGLogicalOffset origin_point =
       opt_origin_point ? opt_origin_point.value() : NGLogicalOffset();
   NGLayoutOpportunity initial_opportunity =
-      CreateLayoutOpportunityFromConstraintSpace(*space, origin_point);
+      CreateLayoutOpportunityFromConstraintSpace(*constraint_space_,
+                                                 origin_point);
   opportunity_tree_root_ = new NGLayoutOpportunityTreeNode(initial_opportunity);
 
   if (opt_leader_point) {
     const NGExclusion leader_exclusion =
         ToLeaderExclusion(origin_point, opt_leader_point.value());
     InsertExclusion(MutableOpportunityTreeRoot(), &leader_exclusion,
                     opportunities_);
   }
 
   for (const auto& exclusion : exclusions->storage) {
     InsertExclusion(MutableOpportunityTreeRoot(), exclusion.get(),
                     opportunities_);
   }
   CollectAllOpportunities(OpportunityTreeRoot(), opportunities_);
   std::sort(opportunities_.begin(), opportunities_.end(),
             &CompareNGLayoutOpportunitesByStartPoint);
 
   opportunity_iter_ = opportunities_.begin();
 }
 
 const NGLayoutOpportunity NGLayoutOpportunityIterator::Next() {
   if (opportunity_iter_ == opportunities_.end())
     return NGLayoutOpportunity();
   auto* opportunity = opportunity_iter_;
   opportunity_iter_++;
   return NGLayoutOpportunity(*opportunity);
 }
 
 }  // namespace blink