[LayoutNG] Introduce NGPositionedFloat.

third_party/WebKit/Source/core/layout/ng/ng_fragment_builder.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_fragment_builder.h"
 
 #include "core/layout/ng/inline/ng_physical_text_fragment.h"
 #include "core/layout/ng/ng_block_break_token.h"
 #include "core/layout/ng/ng_block_node.h"
 #include "core/layout/ng/ng_break_token.h"
@@ skipping 178 matching lines @@
     child_break_tokens_.push_back(std::move(last_inline_break_token_));
     did_break_ = true;
   }
   if (did_break_) {
     break_token = NGBlockBreakToken::Create(node_.Get(), used_block_size_,
                                             child_break_tokens_);
   } else {
     break_token = NGBlockBreakToken::Create(node_.Get());
   }
 
-  for (auto& floating_object : positioned_floats_) {
-    DCHECK(floating_object->logical_offset)
-        << "logical_offset should be set for a positioned float.";
-    NGPhysicalFragment* floating_fragment = floating_object->fragment.Get();
-    floating_fragment->SetOffset(
-        floating_object->logical_offset.value().ConvertToPhysical(
-            writing_mode_, direction_, physical_size,
-            floating_fragment->Size()));
+  for (auto& positioned_float : positioned_floats_) {
+    NGPhysicalFragment* floating_fragment = positioned_float.fragment.Get();
+    floating_fragment->SetOffset(positioned_float.offset.ConvertToPhysical(
+        writing_mode_, direction_, physical_size, floating_fragment->Size()));
   }
 
   RefPtr<NGPhysicalBoxFragment> fragment = AdoptRef(new NGPhysicalBoxFragment(
       node_->GetLayoutObject(), physical_size,
       overflow_.ConvertToPhysical(writing_mode_), children_, positioned_floats_,
       bfc_offset_, end_margin_strut_, std::move(break_token)));
 
   return AdoptRef(
       new NGLayoutResult(std::move(fragment), out_of_flow_descendants_,
                          out_of_flow_positions_, unpositioned_floats_));
 }
 
 }  // namespace blink