[layoutng] Add a shrink-to-fit flag to the constraint space

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"
@@ skipping 76 matching lines @@
   }
 
   // Some layout modes “stretch” their children to a fixed size (e.g. flex,
   // grid). These flags represented whether a layout needs to produce a
   // fragment that satisfies a fixed constraint in the inline and block
   // direction respectively.
   bool IsFixedSizeInline() const { return is_fixed_size_inline_; }
 
   bool IsFixedSizeBlock() const { return is_fixed_size_block_; }
 
+  bool HasForcedShrinkToFit() const { return has_forced_shrink_to_fit_; }

[ikilpatrick, 2016/12/22 00:06:14]

Comment explaining what this does? E.g.

Whether the child should shrink-to-fit if it's inline size is 'auto', instead of
taking up the inline available space.
E.g. this is used for floating, abs-pos, etc.

[ikilpatrick, 2016/12/22 00:06:14]

IsShrinkToFit? to keep in line with other bits?

[cbiesinger, 2016/12/22 03:34:25]

Done (both).

+
   // If specified a layout should produce a Fragment which fragments at the
   // blockSize if possible.
   NGFragmentationType BlockFragmentationType() const;
 
   // 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 NGFragment*);
 
   NGLayoutOpportunityIterator* LayoutOpportunities(
       unsigned clear = kNGClearNone,
       bool for_inline_or_bfc = false);
 
   DEFINE_INLINE_VIRTUAL_TRACE() {}
 
   String ToString() const;
 
  private:
   friend class NGConstraintSpaceBuilder;
   // Default constructor.
   NGConstraintSpace(NGWritingMode,
                     TextDirection,
                     NGLogicalSize available_size,
                     NGLogicalSize percentage_resolution_size,
                     bool is_fixed_size_inline,
                     bool is_fixed_size_block,
+                    bool has_forced_shrink_to_fit,
                     bool is_inline_direction_triggers_scrollbar,
                     bool is_block_direction_triggers_scrollbar,
                     NGFragmentationType block_direction_fragmentation_type,
                     bool is_new_fc,
                     const std::shared_ptr<NGExclusions>& exclusions_);
 
   NGLogicalSize available_size_;
   NGLogicalSize percentage_resolution_size_;
 
   unsigned is_fixed_size_inline_ : 1;
   unsigned is_fixed_size_block_ : 1;
 
+  unsigned has_forced_shrink_to_fit_ : 1;
+
   unsigned is_inline_direction_triggers_scrollbar_ : 1;
   unsigned is_block_direction_triggers_scrollbar_ : 1;
 
   unsigned block_direction_fragmentation_type_ : 2;
 
   // Whether the current constraint space is for the newly established
   // formatting Context
   unsigned is_new_fc_ : 1;
 
   NGLogicalOffset offset_;
   unsigned writing_mode_ : 3;
   unsigned direction_ : 1;
 
   const std::shared_ptr<NGExclusions> exclusions_;
 };
 
 inline std::ostream& operator<<(std::ostream& stream,
                                 const NGConstraintSpace& value) {
   return stream << value.ToString();
 }
 
 }  // namespace blink
 
 #endif  // NGConstraintSpace_h