CS of out-of-flow positioned objects should have is_new_fc == true

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

Index: third_party/WebKit/Source/core/layout/ng/ng_space_utils.cc
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_space_utils.cc b/third_party/WebKit/Source/core/layout/ng/ng_space_utils.cc
index 98ecc61f2ff93e7a3f385b83e735a3d4efcc8128..5da68ef1fb8007696b60821a52288854df6a42fa 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_space_utils.cc
+++ b/third_party/WebKit/Source/core/layout/ng/ng_space_utils.cc
@@ -19,6 +19,10 @@ WTF::Optional<T> OptionalMax(const WTF::Optional<T>& value1,
   return value2;
 }
 
+bool isOutFlowPositioned(const EPosition& position) {

[ikilpatrick, 2017/03/23 16:39:59]

IsOutOfFlowPositioned

[Gleb Lanbin, 2017/03/24 20:10:05]

Done.

+  return position == EPosition::kAbsolute || position == EPosition::kFixed;
+}
+
 }  // namespace
 
 bool IsNewFormattingContextForInFlowBlockLevelChild(
@@ -31,6 +35,9 @@ bool IsNewFormattingContextForInFlowBlockLevelChild(
   //    in a multi-col formatting context).
   //    (https://drafts.csswg.org/css-multicol-1/#valdef-column-span-all)
 
+  if (style.isFloating() || isOutFlowPositioned(style.position()))
+    return true;
+
   if (style.specifiesColumns() || style.containsPaint() ||
       style.containsLayout())
     return true;