[LayoutNG] Stack allocate NGLayoutOpportunityIterator.

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

 // 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.
 
 #ifndef NGConstraintSpace_h
 #define NGConstraintSpace_h
 
 #include "core/CoreExport.h"
 #include "core/layout/ng/ng_units.h"
 #include "core/layout/ng/ng_writing_mode.h"
 #include "platform/heap/Handle.h"
 #include "wtf/Optional.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 class LayoutBox;
 class NGBoxFragment;
-class NGLayoutOpportunityIterator;
 
 enum NGFragmentationType {
   kFragmentNone,
   kFragmentPage,
   kFragmentColumn,
   kFragmentRegion
 };
 
 // The NGConstraintSpace represents a set of constraints and available space
 // which a layout algorithm may produce a NGFragment within.
@@ skipping 72 matching lines @@
   // context.
   bool HasBlockFragmentation() const {
     return BlockFragmentationType() != kFragmentNone;
   }
 
   // Modifies constraint space to account for a placed fragment. Depending on
   // the shape of the fragment this will either modify the inline or block
   // size, or add an exclusion.
   void Subtract(const NGBoxFragment*);
 
-  NGLayoutOpportunityIterator* LayoutOpportunities(
-      const WTF::Optional<NGLogicalOffset>& opt_origin_point = WTF::nullopt);
-
   NGMarginStrut MarginStrut() const { return margin_strut_; }
 
   NGLogicalOffset BfcOffset() const { return bfc_offset_; }
 
   DEFINE_INLINE_VIRTUAL_TRACE() {}
 
   String ToString() const;
 
  private:
   friend class NGConstraintSpaceBuilder;
@@ skipping 42 matching lines @@
 };
 
 inline std::ostream& operator<<(std::ostream& stream,
                                 const NGConstraintSpace& value) {
   return stream << value.ToString();
 }
 
 }  // namespace blink
 
 #endif  // NGConstraintSpace_h