[LayoutNG] Move remaining ng_units structs to their own files

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 "core/layout/ng/ng_exclusion.h"
 #include "wtf/NonCopyingSort.h"
 
 namespace blink {
 namespace {
 
 // Collects all opportunities from leaves of Layout Opportunity spatial tree.
 void CollectAllOpportunities(const NGLayoutOpportunityTreeNode* node,
                              NGLayoutOpportunities& opportunities) {
   if (!node)
     return;
@@ skipping 251 matching lines @@
 
 const NGLayoutOpportunity NGLayoutOpportunityIterator::Next() {
   if (opportunity_iter_ == opportunities_.end())
     return NGLayoutOpportunity();
   auto* opportunity = opportunity_iter_;
   opportunity_iter_++;
   return NGLayoutOpportunity(*opportunity);
 }
 
 }  // namespace blink