[LayoutNG] Refactor of NGLineBreaker.

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

Index: third_party/WebKit/Source/core/layout/ng/ng_constraint_space.cc
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_constraint_space.cc b/third_party/WebKit/Source/core/layout/ng/ng_constraint_space.cc
index 8d088bf6b320a3bda06a7a4b432f74b4821e770c..59a32a267d923f1e19c011951ce26be508b7c3bc 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_constraint_space.cc
+++ b/third_party/WebKit/Source/core/layout/ng/ng_constraint_space.cc
@@ -7,7 +7,6 @@
 #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 {
 
@@ -50,8 +49,7 @@ NGConstraintSpace::NGConstraintSpace(
       margin_strut_(margin_strut),
       bfc_offset_(bfc_offset),
       exclusions_(exclusions),
-      clearance_offset_(clearance_offset),
-      layout_opp_iter_(nullptr) {
+      clearance_offset_(clearance_offset) {
   unpositioned_floats_.swap(unpositioned_floats);
 }
 
@@ -130,26 +128,12 @@ RefPtr<NGConstraintSpace> NGConstraintSpace::CreateFromLayoutObject(
 
 void NGConstraintSpace::AddExclusion(const NGExclusion& exclusion) {
   exclusions_->Add(exclusion);
-  // Invalidate the Layout Opportunity Iterator.
-  layout_opp_iter_.reset();
 }
 
 NGFragmentationType NGConstraintSpace::BlockFragmentationType() const {
   return static_cast<NGFragmentationType>(block_direction_fragmentation_type_);
 }
 
-NGLayoutOpportunityIterator* NGConstraintSpace::LayoutOpportunityIterator(
-    const NGLogicalOffset& iter_offset) {
-  if (layout_opp_iter_ && layout_opp_iter_->Offset() != iter_offset)
-    layout_opp_iter_.reset();
-
-  if (!layout_opp_iter_) {
-    layout_opp_iter_ = WTF::MakeUnique<NGLayoutOpportunityIterator>(
-        Exclusions().get(), AvailableSize(), iter_offset);
-  }
-  return layout_opp_iter_.get();
-}
-
 bool NGConstraintSpace::operator==(const NGConstraintSpace& other) const {
   // TODO(cbiesinger): For simplicity and performance, for now, we only
   // consider two constraint spaces equal if neither one has unpositioned