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

third_party/WebKit/Source/core/layout/ng/ng_constraint_space.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_constraint_space.h"
 
 #include "core/layout/LayoutBlock.h"
 #include "core/layout/LayoutView.h"
 #include "core/layout/ng/ng_constraint_space_builder.h"
 #include "core/layout/ng/ng_layout_opportunity_iterator.h"
 
 namespace blink {
 
 NGConstraintSpace::NGConstraintSpace(
     NGWritingMode writing_mode,
     TextDirection direction,
     NGLogicalSize available_size,
     NGLogicalSize percentage_resolution_size,
     LayoutUnit fragmentainer_space_available,
     bool is_fixed_size_inline,
     bool is_fixed_size_block,
     bool is_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 NGMarginStrut& margin_strut,
+    const NGLogicalOffset& bfc_offset,
     const std::shared_ptr<NGExclusions>& exclusions)
     : available_size_(available_size),
       percentage_resolution_size_(percentage_resolution_size),
       fragmentainer_space_available_(fragmentainer_space_available),
       is_fixed_size_inline_(is_fixed_size_inline),
       is_fixed_size_block_(is_fixed_size_block),
       is_shrink_to_fit_(is_shrink_to_fit),
       is_inline_direction_triggers_scrollbar_(
           is_inline_direction_triggers_scrollbar),
       is_block_direction_triggers_scrollbar_(
           is_block_direction_triggers_scrollbar),
       block_direction_fragmentation_type_(block_direction_fragmentation_type),
       is_new_fc_(is_new_fc),
       writing_mode_(writing_mode),
       direction_(static_cast<unsigned>(direction)),
+      margin_strut_(margin_strut),
+      bfc_offset_(bfc_offset),
       exclusions_(exclusions) {}
 
 NGConstraintSpace* NGConstraintSpace::CreateFromLayoutObject(
     const LayoutBox& box) {
   bool fixed_inline = false, fixed_block = false;
   // XXX for orthogonal writing mode this is not right
   LayoutUnit available_logical_width =
       std::max(LayoutUnit(), box.containingBlockLogicalWidthForContent());
   LayoutUnit available_logical_height;
   if (!box.parent()) {
@@ skipping 45 matching lines @@
 
 NGFragmentationType NGConstraintSpace::BlockFragmentationType() const {
   return static_cast<NGFragmentationType>(block_direction_fragmentation_type_);
 }
 
 void NGConstraintSpace::Subtract(const NGBoxFragment*) {
   // TODO(layout-ng): Implement.
 }
 
 NGLayoutOpportunityIterator* NGConstraintSpace::LayoutOpportunities(
-    unsigned clear,
-    bool for_inline_or_bfc) {
-  NGLayoutOpportunityIterator* iterator = new NGLayoutOpportunityIterator(this);
+    const WTF::Optional<NGLogicalOffset>& opt_origin_point) {
+  NGLayoutOpportunityIterator* iterator =
+      new NGLayoutOpportunityIterator(this, opt_origin_point);
   return iterator;
 }
 
 String NGConstraintSpace::ToString() const {
-  return String::format("%s,%s %sx%s",
-                        offset_.inline_offset.toString().ascii().data(),
-                        offset_.block_offset.toString().ascii().data(),
+  return String::format("Offset: %s,%s Size: %sx%s MarginStrut: %s",
+                        bfc_offset_.inline_offset.toString().ascii().data(),
+                        bfc_offset_.block_offset.toString().ascii().data(),
                         AvailableSize().inline_size.toString().ascii().data(),
-                        AvailableSize().block_size.toString().ascii().data());
+                        AvailableSize().block_size.toString().ascii().data(),
+                        margin_strut_.ToString().ascii().data());
 }
 
 }  // namespace blink