Top down version of algorithm to position margins and floats in LayoutNG

third_party/WebKit/Source/core/layout/ng/ng_fragment_builder.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 NGFragmentBuilder_h
 #define NGFragmentBuilder_h
 
 #include "core/layout/ng/ng_constraint_space.h"
 #include "core/layout/ng/ng_floating_object.h"
 #include "core/layout/ng/ng_physical_fragment.h"
@@ skipping 20 matching lines @@
   NGFragmentBuilder& SetBlockSize(LayoutUnit);
   NGLogicalSize Size() const { return size_; }
 
   NGFragmentBuilder& SetInlineOverflow(LayoutUnit);
   NGFragmentBuilder& SetBlockOverflow(LayoutUnit);
 
   NGFragmentBuilder& AddChild(NGFragment*, const NGLogicalOffset&);
   NGFragmentBuilder& AddFloatingObject(NGFloatingObject*,
                                        const NGLogicalOffset&);
 
+  NGFragmentBuilder& SetBfcOffset(const NGLogicalOffset& offset);
+
+  NGFragmentBuilder& AddUnpositionedFloat(NGFloatingObject* floating_object);
+
   // Builder has non-trivial out-of-flow descendant methods.
   // These methods are building blocks for implementation of
   // out-of-flow descendants by layout algorithms.
   //
   // They are intended to be used by layout algorithm like this:
   //
   // Part 1: layout algorithm positions in-flow children.
   //   out-of-flow children, and out-of-flow descendants of fragments
   //   are stored inside builder.
   //
@@ skipping 13 matching lines @@
   //
   // See layout part for builder interaction.
   NGFragmentBuilder& AddOutOfFlowChildCandidate(NGBlockNode*, NGLogicalOffset);
 
   void GetAndClearOutOfFlowDescendantCandidates(WeakBoxList*,
                                                 Vector<NGStaticPosition>*);
 
   NGFragmentBuilder& AddOutOfFlowDescendant(NGBlockNode*,
                                             const NGStaticPosition&);
 
-  NGFragmentBuilder& AddUnpositionedFloat(NGFloatingObject* floating_object);
-
   void SetBreakToken(NGBreakToken* token) {
     DCHECK(!break_token_);
     break_token_ = token;
   }
   bool HasBreakToken() const { return break_token_; }
 
-  // Sets MarginStrut for the resultant fragment.
-  NGFragmentBuilder& SetMarginStrutBlockStart(
-      const NGDeprecatedMarginStrut& from);
-  NGFragmentBuilder& SetMarginStrutBlockEnd(
-      const NGDeprecatedMarginStrut& from);
+  NGFragmentBuilder& SetEndMarginStrut(const NGMarginStrut& from) {
+    end_margin_strut_ = from;
+    return *this;
+  }
 
   // Offsets are not supposed to be set during fragment construction, so we
   // do not provide a setter here.
 
   // Creates the fragment. Can only be called once.
   NGPhysicalBoxFragment* ToBoxFragment();
   NGPhysicalTextFragment* ToTextFragment(NGInlineNode*,
                                          unsigned start_index,
                                          unsigned end_index);
 
+  // Mutable list of floats that need to be positioned.
+  HeapVector<Member<NGFloatingObject>>& MutableUnpositionedFloats() {
+    return unpositioned_floats_;
+  }
+
   // List of floats that need to be positioned.
-  HeapVector<Member<NGFloatingObject>>& UnpositionedFloats() {
+  const HeapVector<Member<NGFloatingObject>>& UnpositionedFloats() const {
     return unpositioned_floats_;
   }
 
+  const WTF::Optional<NGLogicalOffset>& BfcOffset() const {
+    return bfc_offset_;
+  }
+
   DECLARE_VIRTUAL_TRACE();
 
- private:
   // Out-of-flow descendant placement information.
   // The generated fragment must compute NGStaticPosition for all
   // out-of-flow descendants.
   // The resulting NGStaticPosition gets derived from:
   // 1. The offset of fragment's child.
   // 2. The static position of descendant wrt child.
   //
   // A child can be:
   // 1. A descendant itself. In this case, descendant position is (0,0).
   // 2. A fragment containing a descendant.
   //
   // child_offset is stored as NGLogicalOffset because physical offset cannot
   // be computed until we know fragment's size.
   struct OutOfFlowPlacement {
     NGLogicalOffset child_offset;
     NGStaticPosition descendant_position;
   };
 
   NGPhysicalFragment::NGFragmentType type_;
   NGWritingMode writing_mode_;
   TextDirection direction_;
 
   LayoutObject* layout_object_;
 
   NGLogicalSize size_;
   NGLogicalSize overflow_;
 
-  NGDeprecatedMarginStrut margin_strut_;
-
   HeapVector<Member<NGPhysicalFragment>> children_;
   Vector<NGLogicalOffset> offsets_;
 
   WeakBoxList out_of_flow_descendant_candidates_;
   Vector<OutOfFlowPlacement> out_of_flow_candidate_placements_;
 
   WeakBoxList out_of_flow_descendants_;
   Vector<NGStaticPosition> out_of_flow_positions_;
 
   // Floats that need to be positioned by the next in-flow fragment that can
   // determine its block position in space.
   HeapVector<Member<NGFloatingObject>> unpositioned_floats_;
 
   Vector<NGLogicalOffset> floating_object_offsets_;
   HeapVector<Member<NGFloatingObject>> positioned_floats_;
 
   Member<NGBreakToken> break_token_;
+
+  WTF::Optional<NGLogicalOffset> bfc_offset_;
+  NGMarginStrut end_margin_strut_;
 };
 
 }  // namespace blink
 
 #endif  // NGFragmentBuilder