Place the out of flow positioned blocks

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

Index: third_party/WebKit/Source/core/layout/ng/ng_units.h
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_units.h b/third_party/WebKit/Source/core/layout/ng/ng_units.h
index 6c768d7916b05a5f7799712020bc1155250ed21e..63bd0b37175a569d88d98a42e5479cdf1c1e5a96 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_units.h
+++ b/third_party/WebKit/Source/core/layout/ng/ng_units.h
@@ -105,6 +105,8 @@ struct NGPhysicalOffset {
 
   NGPhysicalOffset operator+(const NGPhysicalOffset& other) const;
   NGPhysicalOffset& operator+=(const NGPhysicalOffset& other);
+  NGPhysicalOffset operator-(const NGPhysicalOffset& other) const;
+  NGPhysicalOffset& operator-=(const NGPhysicalOffset& other);
 };
 
 struct NGPhysicalSize {
@@ -310,7 +312,6 @@ struct CORE_EXPORT NGStaticPosition {
   static NGStaticPosition Create(NGWritingMode,
                                  TextDirection,
                                  NGPhysicalOffset);
-
   // Left/Right/TopPosition functions map static position to
   // left/right/top edge wrt container space.
   // The function arguments are required to solve the equation: