[LayoutNG] Allow block-flow layout to be fragmented using new approach.

third_party/WebKit/Source/core/layout/ng/ng_constraint_space_builder.h

Index: third_party/WebKit/Source/core/layout/ng/ng_constraint_space_builder.h
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_constraint_space_builder.h b/third_party/WebKit/Source/core/layout/ng/ng_constraint_space_builder.h
index 61549af0b465dfc9239989189ac5753feba64e9b..c8b387d6fa23d39842e69c3a74ff370bd5441b8d 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_constraint_space_builder.h
+++ b/third_party/WebKit/Source/core/layout/ng/ng_constraint_space_builder.h
@@ -43,6 +43,7 @@ class CORE_EXPORT NGConstraintSpaceBuilder final
 
   NGConstraintSpaceBuilder& SetFragmentationType(NGFragmentationType);
   NGConstraintSpaceBuilder& SetIsNewFormattingContext(bool is_new_fc);
+  NGConstraintSpaceBuilder& SetIsAnonymous(bool is_anonymous);

[mstensho (USE GERRIT), 2017/02/27 13:44:36]

Does it ever make sense to pass false here? I.e. could we just remove the
parameter, perhaps?

[ikilpatrick, 2017/02/27 18:50:09]

So the constraint space builder can be re-used for multiple children. In
multi-cols case, if we see a spanner we'll probably want to set this to false?

[mstensho (USE GERRIT), 2017/02/27 20:28:20]

Acknowledged.

 
   NGConstraintSpaceBuilder& SetMarginStrut(const NGMarginStrut& margin_strut);
 
@@ -79,6 +80,7 @@ class CORE_EXPORT NGConstraintSpaceBuilder final
   unsigned is_block_direction_triggers_scrollbar_ : 1;
   unsigned fragmentation_type_ : 2;
   unsigned is_new_fc_ : 1;
+  unsigned is_anonymous_ : 1;
   unsigned text_direction_ : 1;
 
   NGMarginStrut margin_strut_;